diff options
Diffstat (limited to 'net/dccp')
36 files changed, 8922 insertions, 5136 deletions
diff --git a/net/dccp/Kconfig b/net/dccp/Kconfig index 187ac182e24..8c0ef71bed2 100644 --- a/net/dccp/Kconfig +++ b/net/dccp/Kconfig @@ -1,50 +1,62 @@ -menu "DCCP Configuration (EXPERIMENTAL)" - depends on INET && EXPERIMENTAL - -config IP_DCCP - tristate "The DCCP Protocol (EXPERIMENTAL)" +menuconfig IP_DCCP + tristate "The DCCP Protocol" + depends on INET ---help--- - Datagram Congestion Control Protocol + Datagram Congestion Control Protocol (RFC 4340) - From draft-ietf-dccp-spec-11 <http://www.icir.org/kohler/dcp/draft-ietf-dccp-spec-11.txt>. + From http://www.ietf.org/rfc/rfc4340.txt: The Datagram Congestion Control Protocol (DCCP) is a transport protocol that implements bidirectional, unicast connections of congestion-controlled, unreliable datagrams. It should be suitable for use by applications such as streaming media, Internet telephony, - and on-line games + and on-line games. To compile this protocol support as a module, choose M here: the module will be called dccp. If in doubt, say N. +if IP_DCCP + config INET_DCCP_DIAG - depends on IP_DCCP && INET_DIAG + depends on INET_DIAG def_tristate y if (IP_DCCP = y && INET_DIAG = y) def_tristate m source "net/dccp/ccids/Kconfig" menu "DCCP Kernel Hacking" - depends on IP_DCCP && DEBUG_KERNEL=y + depends on DEBUG_KERNEL=y config IP_DCCP_DEBUG bool "DCCP debug messages" ---help--- Only use this if you're hacking DCCP. + When compiling DCCP as a module, this debugging output can be toggled + by setting the parameter dccp_debug of the `dccp' module to 0 or 1. + Just say N. -config IP_DCCP_UNLOAD_HACK - depends on IP_DCCP=m && IP_DCCP_CCID3=m - bool "DCCP control sock unload hack" +config NET_DCCPPROBE + tristate "DCCP connection probing" + depends on PROC_FS && KPROBES ---help--- - Enable this to be able to unload the dccp module when the it - has only one refcount held, the control sock one. Just execute - "rmmod dccp_ccid3 dccp" + This module allows for capturing the changes to DCCP connection + state in response to incoming packets. It is used for debugging + DCCP congestion avoidance modules. If you don't understand + what was just said, you don't need it: say N. + + Documentation on how to use DCCP connection probing can be found + at: + + http://www.linuxfoundation.org/collaborate/workgroups/networking/dccpprobe + + To compile this code as a module, choose M here: the + module will be called dccp_probe. - Just say N. -endmenu endmenu + +endif # IP_DDCP diff --git a/net/dccp/Makefile b/net/dccp/Makefile index 87b27fff6e3..5c8362b037e 100644 --- a/net/dccp/Makefile +++ b/net/dccp/Makefile @@ -1,16 +1,28 @@ -obj-$(CONFIG_IPV6) += dccp_ipv6.o +obj-$(CONFIG_IP_DCCP) += dccp.o dccp_ipv4.o -dccp_ipv6-y := ipv6.o - -obj-$(CONFIG_IP_DCCP) += dccp.o +dccp-y := ccid.o feat.o input.o minisocks.o options.o output.o proto.o timer.o \ + qpolicy.o +# +# CCID algorithms to be used by dccp.ko +# +# CCID-2 is default (RFC 4340, p. 77) and has Ack Vectors as dependency +dccp-y += ccids/ccid2.o ackvec.o +dccp-$(CONFIG_IP_DCCP_CCID3) += ccids/ccid3.o +dccp-$(CONFIG_IP_DCCP_TFRC_LIB) += ccids/lib/tfrc.o \ + ccids/lib/tfrc_equation.o \ + ccids/lib/packet_history.o \ + ccids/lib/loss_interval.o -dccp-y := ccid.o input.o ipv4.o minisocks.o options.o output.o proto.o \ - timer.o +dccp_ipv4-y := ipv4.o -dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o +# build dccp_ipv6 as module whenever either IPv6 or DCCP is a module +obj-$(subst y,$(CONFIG_IP_DCCP),$(CONFIG_IPV6)) += dccp_ipv6.o +dccp_ipv6-y := ipv6.o obj-$(CONFIG_INET_DCCP_DIAG) += dccp_diag.o +obj-$(CONFIG_NET_DCCPPROBE) += dccp_probe.o -dccp_diag-y := diag.o +dccp-$(CONFIG_SYSCTL) += sysctl.o -obj-y += ccids/ +dccp_diag-y := diag.o +dccp_probe-y := probe.o diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c index ce9cb77c5c2..ba07824af4c 100644 --- a/net/dccp/ackvec.c +++ b/net/dccp/ackvec.c @@ -1,426 +1,409 @@ /* * net/dccp/ackvec.c * - * An implementation of the DCCP protocol + * An implementation of Ack Vectors for the DCCP protocol + * Copyright (c) 2007 University of Aberdeen, Scotland, UK * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; version 2 of the License; */ - -#include "ackvec.h" #include "dccp.h" +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/export.h> -#include <linux/dccp.h> -#include <linux/skbuff.h> - -#include <net/sock.h> +static struct kmem_cache *dccp_ackvec_slab; +static struct kmem_cache *dccp_ackvec_record_slab; -int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb) +struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority) { - struct dccp_sock *dp = dccp_sk(sk); - struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec; - int len = av->dccpav_vec_len + 2; - struct timeval now; - u32 elapsed_time; - unsigned char *to, *from; - - dccp_timestamp(sk, &now); - elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10; - - if (elapsed_time != 0) - dccp_insert_option_elapsed_time(sk, skb, elapsed_time); + struct dccp_ackvec *av = kmem_cache_zalloc(dccp_ackvec_slab, priority); - if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) - return -1; - - /* - * XXX: now we have just one ack vector sent record, so - * we have to wait for it to be cleared. - * - * Of course this is not acceptable, but this is just for - * basic testing now. - */ - if (av->dccpav_ack_seqno != DCCP_MAX_SEQNO + 1) - return -1; + if (av != NULL) { + av->av_buf_head = av->av_buf_tail = DCCPAV_MAX_ACKVEC_LEN - 1; + INIT_LIST_HEAD(&av->av_records); + } + return av; +} - DCCP_SKB_CB(skb)->dccpd_opt_len += len; +static void dccp_ackvec_purge_records(struct dccp_ackvec *av) +{ + struct dccp_ackvec_record *cur, *next; - to = skb_push(skb, len); - *to++ = DCCPO_ACK_VECTOR_0; - *to++ = len; + list_for_each_entry_safe(cur, next, &av->av_records, avr_node) + kmem_cache_free(dccp_ackvec_record_slab, cur); + INIT_LIST_HEAD(&av->av_records); +} - len = av->dccpav_vec_len; - from = av->dccpav_buf + av->dccpav_buf_head; +void dccp_ackvec_free(struct dccp_ackvec *av) +{ + if (likely(av != NULL)) { + dccp_ackvec_purge_records(av); + kmem_cache_free(dccp_ackvec_slab, av); + } +} - /* Check if buf_head wraps */ - if ((int)av->dccpav_buf_head + len > av->dccpav_vec_len) { - const u32 tailsize = av->dccpav_vec_len - av->dccpav_buf_head; +/** + * dccp_ackvec_update_records - Record information about sent Ack Vectors + * @av: Ack Vector records to update + * @seqno: Sequence number of the packet carrying the Ack Vector just sent + * @nonce_sum: The sum of all buffer nonces contained in the Ack Vector + */ +int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seqno, u8 nonce_sum) +{ + struct dccp_ackvec_record *avr; - memcpy(to, from, tailsize); - to += tailsize; - len -= tailsize; - from = av->dccpav_buf; - } + avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC); + if (avr == NULL) + return -ENOBUFS; - memcpy(to, from, len); + avr->avr_ack_seqno = seqno; + avr->avr_ack_ptr = av->av_buf_head; + avr->avr_ack_ackno = av->av_buf_ackno; + avr->avr_ack_nonce = nonce_sum; + avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head); /* - * From draft-ietf-dccp-spec-11.txt: - * - * For each acknowledgement it sends, the HC-Receiver will add an - * acknowledgement record. ack_seqno will equal the HC-Receiver - * sequence number it used for the ack packet; ack_ptr will equal - * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will - * equal buf_nonce. - * - * This implemention uses just one ack record for now. + * When the buffer overflows, we keep no more than one record. This is + * the simplest way of disambiguating sender-Acks dating from before the + * overflow from sender-Acks which refer to after the overflow; a simple + * solution is preferable here since we are handling an exception. */ - av->dccpav_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq; - av->dccpav_ack_ptr = av->dccpav_buf_head; - av->dccpav_ack_ackno = av->dccpav_buf_ackno; - av->dccpav_ack_nonce = av->dccpav_buf_nonce; - av->dccpav_sent_len = av->dccpav_vec_len; - - dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, " - "ack_ackno=%llu\n", - debug_prefix, av->dccpav_sent_len, - (unsigned long long)av->dccpav_ack_seqno, - (unsigned long long)av->dccpav_ack_ackno); - return -1; + if (av->av_overflow) + dccp_ackvec_purge_records(av); + /* + * Since GSS is incremented for each packet, the list is automatically + * arranged in descending order of @ack_seqno. + */ + list_add(&avr->avr_node, &av->av_records); + + dccp_pr_debug("Added Vector, ack_seqno=%llu, ack_ackno=%llu (rl=%u)\n", + (unsigned long long)avr->avr_ack_seqno, + (unsigned long long)avr->avr_ack_ackno, + avr->avr_ack_runlen); + return 0; } -struct dccp_ackvec *dccp_ackvec_alloc(const unsigned int len, - const gfp_t priority) +static struct dccp_ackvec_record *dccp_ackvec_lookup(struct list_head *av_list, + const u64 ackno) { - struct dccp_ackvec *av; - - BUG_ON(len == 0); - - if (len > DCCP_MAX_ACKVEC_LEN) - return NULL; - - av = kmalloc(sizeof(*av) + len, priority); - if (av != NULL) { - av->dccpav_buf_len = len; - av->dccpav_buf_head = - av->dccpav_buf_tail = av->dccpav_buf_len - 1; - av->dccpav_buf_ackno = - av->dccpav_ack_ackno = av->dccpav_ack_seqno = ~0LLU; - av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0; - av->dccpav_ack_ptr = 0; - av->dccpav_time.tv_sec = 0; - av->dccpav_time.tv_usec = 0; - av->dccpav_sent_len = av->dccpav_vec_len = 0; + struct dccp_ackvec_record *avr; + /* + * Exploit that records are inserted in descending order of sequence + * number, start with the oldest record first. If @ackno is `before' + * the earliest ack_ackno, the packet is too old to be considered. + */ + list_for_each_entry_reverse(avr, av_list, avr_node) { + if (avr->avr_ack_seqno == ackno) + return avr; + if (before48(ackno, avr->avr_ack_seqno)) + break; } - - return av; + return NULL; } -void dccp_ackvec_free(struct dccp_ackvec *av) +/* + * Buffer index and length computation using modulo-buffersize arithmetic. + * Note that, as pointers move from right to left, head is `before' tail. + */ +static inline u16 __ackvec_idx_add(const u16 a, const u16 b) { - kfree(av); + return (a + b) % DCCPAV_MAX_ACKVEC_LEN; } -static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av, - const u8 index) +static inline u16 __ackvec_idx_sub(const u16 a, const u16 b) { - return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK; + return __ackvec_idx_add(a, DCCPAV_MAX_ACKVEC_LEN - b); } -static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av, - const u8 index) +u16 dccp_ackvec_buflen(const struct dccp_ackvec *av) { - return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK; + if (unlikely(av->av_overflow)) + return DCCPAV_MAX_ACKVEC_LEN; + return __ackvec_idx_sub(av->av_buf_tail, av->av_buf_head); } -/* - * If several packets are missing, the HC-Receiver may prefer to enter multiple - * bytes with run length 0, rather than a single byte with a larger run length; - * this simplifies table updates if one of the missing packets arrives. +/** + * dccp_ackvec_update_old - Update previous state as per RFC 4340, 11.4.1 + * @av: non-empty buffer to update + * @distance: negative or zero distance of @seqno from buf_ackno downward + * @seqno: the (old) sequence number whose record is to be updated + * @state: state in which packet carrying @seqno was received */ -static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av, - const unsigned int packets, - const unsigned char state) +static void dccp_ackvec_update_old(struct dccp_ackvec *av, s64 distance, + u64 seqno, enum dccp_ackvec_states state) { - unsigned int gap; - signed long new_head; + u16 ptr = av->av_buf_head; - if (av->dccpav_vec_len + packets > av->dccpav_buf_len) - return -ENOBUFS; + BUG_ON(distance > 0); + if (unlikely(dccp_ackvec_is_empty(av))) + return; - gap = packets - 1; - new_head = av->dccpav_buf_head - packets; + do { + u8 runlen = dccp_ackvec_runlen(av->av_buf + ptr); - if (new_head < 0) { - if (gap > 0) { - memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED, - gap + new_head + 1); - gap = -new_head; + if (distance + runlen >= 0) { + /* + * Only update the state if packet has not been received + * yet. This is OK as per the second table in RFC 4340, + * 11.4.1; i.e. here we are using the following table: + * RECEIVED + * 0 1 3 + * S +---+---+---+ + * T 0 | 0 | 0 | 0 | + * O +---+---+---+ + * R 1 | 1 | 1 | 1 | + * E +---+---+---+ + * D 3 | 0 | 1 | 3 | + * +---+---+---+ + * The "Not Received" state was set by reserve_seats(). + */ + if (av->av_buf[ptr] == DCCPAV_NOT_RECEIVED) + av->av_buf[ptr] = state; + else + dccp_pr_debug("Not changing %llu state to %u\n", + (unsigned long long)seqno, state); + break; } - new_head += av->dccpav_buf_len; - } - av->dccpav_buf_head = new_head; + distance += runlen + 1; + ptr = __ackvec_idx_add(ptr, 1); - if (gap > 0) - memset(av->dccpav_buf + av->dccpav_buf_head + 1, - DCCP_ACKVEC_STATE_NOT_RECEIVED, gap); + } while (ptr != av->av_buf_tail); +} - av->dccpav_buf[av->dccpav_buf_head] = state; - av->dccpav_vec_len += packets; - return 0; +/* Mark @num entries after buf_head as "Not yet received". */ +static void dccp_ackvec_reserve_seats(struct dccp_ackvec *av, u16 num) +{ + u16 start = __ackvec_idx_add(av->av_buf_head, 1), + len = DCCPAV_MAX_ACKVEC_LEN - start; + + /* check for buffer wrap-around */ + if (num > len) { + memset(av->av_buf + start, DCCPAV_NOT_RECEIVED, len); + start = 0; + num -= len; + } + if (num) + memset(av->av_buf + start, DCCPAV_NOT_RECEIVED, num); } -/* - * Implements the draft-ietf-dccp-spec-11.txt Appendix A +/** + * dccp_ackvec_add_new - Record one or more new entries in Ack Vector buffer + * @av: container of buffer to update (can be empty or non-empty) + * @num_packets: number of packets to register (must be >= 1) + * @seqno: sequence number of the first packet in @num_packets + * @state: state in which packet carrying @seqno was received */ -int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk, - const u64 ackno, const u8 state) +static void dccp_ackvec_add_new(struct dccp_ackvec *av, u32 num_packets, + u64 seqno, enum dccp_ackvec_states state) { - /* - * Check at the right places if the buffer is full, if it is, tell the - * caller to start dropping packets till the HC-Sender acks our ACK - * vectors, when we will free up space in dccpav_buf. - * - * We may well decide to do buffer compression, etc, but for now lets - * just drop. - * - * From Appendix A: - * - * Of course, the circular buffer may overflow, either when the - * HC-Sender is sending data at a very high rate, when the - * HC-Receiver's acknowledgements are not reaching the HC-Sender, - * or when the HC-Sender is forgetting to acknowledge those acks - * (so the HC-Receiver is unable to clean up old state). In this - * case, the HC-Receiver should either compress the buffer (by - * increasing run lengths when possible), transfer its state to - * a larger buffer, or, as a last resort, drop all received - * packets, without processing them whatsoever, until its buffer - * shrinks again. - */ + u32 num_cells = num_packets; - /* See if this is the first ackno being inserted */ - if (av->dccpav_vec_len == 0) { - av->dccpav_buf[av->dccpav_buf_head] = state; - av->dccpav_vec_len = 1; - } else if (after48(ackno, av->dccpav_buf_ackno)) { - const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno, - ackno); + if (num_packets > DCCPAV_BURST_THRESH) { + u32 lost_packets = num_packets - 1; + DCCP_WARN("Warning: large burst loss (%u)\n", lost_packets); /* - * Look if the state of this packet is the same as the - * previous ackno and if so if we can bump the head len. - */ - if (delta == 1 && - dccp_ackvec_state(av, av->dccpav_buf_head) == state && - (dccp_ackvec_len(av, av->dccpav_buf_head) < - DCCP_ACKVEC_LEN_MASK)) - av->dccpav_buf[av->dccpav_buf_head]++; - else if (dccp_ackvec_set_buf_head_state(av, delta, state)) - return -ENOBUFS; - } else { - /* - * A.1.2. Old Packets - * - * When a packet with Sequence Number S arrives, and - * S <= buf_ackno, the HC-Receiver will scan the table - * for the byte corresponding to S. (Indexing structures - * could reduce the complexity of this scan.) + * We received 1 packet and have a loss of size "num_packets-1" + * which we squeeze into num_cells-1 rather than reserving an + * entire byte for each lost packet. + * The reason is that the vector grows in O(burst_length); when + * it grows too large there will no room left for the payload. + * This is a trade-off: if a few packets out of the burst show + * up later, their state will not be changed; it is simply too + * costly to reshuffle/reallocate/copy the buffer each time. + * Should such problems persist, we will need to switch to a + * different underlying data structure. */ - u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno); - u8 index = av->dccpav_buf_head; + for (num_packets = num_cells = 1; lost_packets; ++num_cells) { + u8 len = min(lost_packets, (u32)DCCPAV_MAX_RUNLEN); - while (1) { - const u8 len = dccp_ackvec_len(av, index); - const u8 state = dccp_ackvec_state(av, index); - /* - * valid packets not yet in dccpav_buf have a reserved - * entry, with a len equal to 0. - */ - if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED && - len == 0 && delta == 0) { /* Found our - reserved seat! */ - dccp_pr_debug("Found %llu reserved seat!\n", - (unsigned long long)ackno); - av->dccpav_buf[index] = state; - goto out; - } - /* len == 0 means one packet */ - if (delta < len + 1) - goto out_duplicate; - - delta -= len + 1; - if (++index == av->dccpav_buf_len) - index = 0; + av->av_buf_head = __ackvec_idx_sub(av->av_buf_head, 1); + av->av_buf[av->av_buf_head] = DCCPAV_NOT_RECEIVED | len; + + lost_packets -= len; } } - av->dccpav_buf_ackno = ackno; - dccp_timestamp(sk, &av->dccpav_time); -out: - dccp_pr_debug(""); - return 0; + if (num_cells + dccp_ackvec_buflen(av) >= DCCPAV_MAX_ACKVEC_LEN) { + DCCP_CRIT("Ack Vector buffer overflow: dropping old entries\n"); + av->av_overflow = true; + } + + av->av_buf_head = __ackvec_idx_sub(av->av_buf_head, num_packets); + if (av->av_overflow) + av->av_buf_tail = av->av_buf_head; -out_duplicate: - /* Duplicate packet */ - dccp_pr_debug("Received a dup or already considered lost " - "packet: %llu\n", (unsigned long long)ackno); - return -EILSEQ; + av->av_buf[av->av_buf_head] = state; + av->av_buf_ackno = seqno; + + if (num_packets > 1) + dccp_ackvec_reserve_seats(av, num_packets - 1); } -#ifdef CONFIG_IP_DCCP_DEBUG -void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len) +/** + * dccp_ackvec_input - Register incoming packet in the buffer + */ +void dccp_ackvec_input(struct dccp_ackvec *av, struct sk_buff *skb) { - if (!dccp_debug) - return; + u64 seqno = DCCP_SKB_CB(skb)->dccpd_seq; + enum dccp_ackvec_states state = DCCPAV_RECEIVED; - printk("ACK vector len=%d, ackno=%llu |", len, - (unsigned long long)ackno); + if (dccp_ackvec_is_empty(av)) { + dccp_ackvec_add_new(av, 1, seqno, state); + av->av_tail_ackno = seqno; - while (len--) { - const u8 state = (*vector & DCCP_ACKVEC_STATE_MASK) >> 6; - const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; + } else { + s64 num_packets = dccp_delta_seqno(av->av_buf_ackno, seqno); + u8 *current_head = av->av_buf + av->av_buf_head; - printk("%d,%d|", state, rl); - ++vector; - } + if (num_packets == 1 && + dccp_ackvec_state(current_head) == state && + dccp_ackvec_runlen(current_head) < DCCPAV_MAX_RUNLEN) { - printk("\n"); -} + *current_head += 1; + av->av_buf_ackno = seqno; -void dccp_ackvec_print(const struct dccp_ackvec *av) -{ - dccp_ackvector_print(av->dccpav_buf_ackno, - av->dccpav_buf + av->dccpav_buf_head, - av->dccpav_vec_len); + } else if (num_packets > 0) { + dccp_ackvec_add_new(av, num_packets, seqno, state); + } else { + dccp_ackvec_update_old(av, num_packets, seqno, state); + } + } } -#endif -static void dccp_ackvec_throw_away_ack_record(struct dccp_ackvec *av) +/** + * dccp_ackvec_clear_state - Perform house-keeping / garbage-collection + * This routine is called when the peer acknowledges the receipt of Ack Vectors + * up to and including @ackno. While based on on section A.3 of RFC 4340, here + * are additional precautions to prevent corrupted buffer state. In particular, + * we use tail_ackno to identify outdated records; it always marks the earliest + * packet of group (2) in 11.4.2. + */ +void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno) { + struct dccp_ackvec_record *avr, *next; + u8 runlen_now, eff_runlen; + s64 delta; + + avr = dccp_ackvec_lookup(&av->av_records, ackno); + if (avr == NULL) + return; /* - * As we're keeping track of the ack vector size (dccpav_vec_len) and - * the sent ack vector size (dccpav_sent_len) we don't need - * dccpav_buf_tail at all, but keep this code here as in the future - * we'll implement a vector of ack records, as suggested in - * draft-ietf-dccp-spec-11.txt Appendix A. -acme + * Deal with outdated acknowledgments: this arises when e.g. there are + * several old records and the acks from the peer come in slowly. In + * that case we may still have records that pre-date tail_ackno. */ -#if 0 - u32 new_buf_tail = av->dccpav_ack_ptr + 1; - if (new_buf_tail >= av->dccpav_vec_len) - new_buf_tail -= av->dccpav_vec_len; - av->dccpav_buf_tail = new_buf_tail; -#endif - av->dccpav_vec_len -= av->dccpav_sent_len; -} + delta = dccp_delta_seqno(av->av_tail_ackno, avr->avr_ack_ackno); + if (delta < 0) + goto free_records; + /* + * Deal with overlapping Ack Vectors: don't subtract more than the + * number of packets between tail_ackno and ack_ackno. + */ + eff_runlen = delta < avr->avr_ack_runlen ? delta : avr->avr_ack_runlen; -void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk, - const u64 ackno) -{ - /* Check if we actually sent an ACK vector */ - if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1) - return; + runlen_now = dccp_ackvec_runlen(av->av_buf + avr->avr_ack_ptr); + /* + * The run length of Ack Vector cells does not decrease over time. If + * the run length is the same as at the time the Ack Vector was sent, we + * free the ack_ptr cell. That cell can however not be freed if the run + * length has increased: in this case we need to move the tail pointer + * backwards (towards higher indices), to its next-oldest neighbour. + */ + if (runlen_now > eff_runlen) { - if (ackno == av->dccpav_ack_seqno) { -#ifdef CONFIG_IP_DCCP_DEBUG - struct dccp_sock *dp = dccp_sk(sk); - const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? - "CLIENT rx ack: " : "server rx ack: "; -#endif - dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, " - "ack_ackno=%llu, ACKED!\n", - debug_prefix, 1, - (unsigned long long)av->dccpav_ack_seqno, - (unsigned long long)av->dccpav_ack_ackno); - dccp_ackvec_throw_away_ack_record(av); - av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1; - } -} + av->av_buf[avr->avr_ack_ptr] -= eff_runlen + 1; + av->av_buf_tail = __ackvec_idx_add(avr->avr_ack_ptr, 1); -static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av, - struct sock *sk, u64 ackno, - const unsigned char len, - const unsigned char *vector) -{ - unsigned char i; + /* This move may not have cleared the overflow flag. */ + if (av->av_overflow) + av->av_overflow = (av->av_buf_head == av->av_buf_tail); + } else { + av->av_buf_tail = avr->avr_ack_ptr; + /* + * We have made sure that avr points to a valid cell within the + * buffer. This cell is either older than head, or equals head + * (empty buffer): in both cases we no longer have any overflow. + */ + av->av_overflow = 0; + } - /* Check if we actually sent an ACK vector */ - if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1) - return; /* - * We're in the receiver half connection, so if the received an ACK - * vector ackno (e.g. 50) before dccpav_ack_seqno (e.g. 52), we're - * not interested. - * - * Extra explanation with example: - * - * if we received an ACK vector with ackno 50, it can only be acking - * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent). + * The peer has acknowledged up to and including ack_ackno. Hence the + * first packet in group (2) of 11.4.2 is the successor of ack_ackno. */ - /* dccp_pr_debug("is %llu < %llu? ", ackno, av->dccpav_ack_seqno); */ - if (before48(ackno, av->dccpav_ack_seqno)) { - /* dccp_pr_debug_cat("yes\n"); */ - return; + av->av_tail_ackno = ADD48(avr->avr_ack_ackno, 1); + +free_records: + list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) { + list_del(&avr->avr_node); + kmem_cache_free(dccp_ackvec_record_slab, avr); } - /* dccp_pr_debug_cat("no\n"); */ +} - i = len; - while (i--) { - const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; - u64 ackno_end_rl; +/* + * Routines to keep track of Ack Vectors received in an skb + */ +int dccp_ackvec_parsed_add(struct list_head *head, u8 *vec, u8 len, u8 nonce) +{ + struct dccp_ackvec_parsed *new = kmalloc(sizeof(*new), GFP_ATOMIC); - dccp_set_seqno(&ackno_end_rl, ackno - rl); + if (new == NULL) + return -ENOBUFS; + new->vec = vec; + new->len = len; + new->nonce = nonce; - /* - * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl, - * av->dccpav_ack_seqno, ackno); - */ - if (between48(av->dccpav_ack_seqno, ackno_end_rl, ackno)) { - const u8 state = (*vector & - DCCP_ACKVEC_STATE_MASK) >> 6; - /* dccp_pr_debug_cat("yes\n"); */ - - if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) { -#ifdef CONFIG_IP_DCCP_DEBUG - struct dccp_sock *dp = dccp_sk(sk); - const char *debug_prefix = - dp->dccps_role == DCCP_ROLE_CLIENT ? - "CLIENT rx ack: " : "server rx ack: "; -#endif - dccp_pr_debug("%sACK vector 0, len=%d, " - "ack_seqno=%llu, ack_ackno=%llu, " - "ACKED!\n", - debug_prefix, len, - (unsigned long long) - av->dccpav_ack_seqno, - (unsigned long long) - av->dccpav_ack_ackno); - dccp_ackvec_throw_away_ack_record(av); - } - /* - * If dccpav_ack_seqno was not received, no problem - * we'll send another ACK vector. - */ - av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1; - break; - } - /* dccp_pr_debug_cat("no\n"); */ + list_add_tail(&new->node, head); + return 0; +} +EXPORT_SYMBOL_GPL(dccp_ackvec_parsed_add); - dccp_set_seqno(&ackno, ackno_end_rl - 1); - ++vector; - } +void dccp_ackvec_parsed_cleanup(struct list_head *parsed_chunks) +{ + struct dccp_ackvec_parsed *cur, *next; + + list_for_each_entry_safe(cur, next, parsed_chunks, node) + kfree(cur); + INIT_LIST_HEAD(parsed_chunks); } +EXPORT_SYMBOL_GPL(dccp_ackvec_parsed_cleanup); -int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb, - const u8 opt, const u8 *value, const u8 len) +int __init dccp_ackvec_init(void) { - if (len > DCCP_MAX_ACKVEC_LEN) - return -1; + dccp_ackvec_slab = kmem_cache_create("dccp_ackvec", + sizeof(struct dccp_ackvec), 0, + SLAB_HWCACHE_ALIGN, NULL); + if (dccp_ackvec_slab == NULL) + goto out_err; + + dccp_ackvec_record_slab = kmem_cache_create("dccp_ackvec_record", + sizeof(struct dccp_ackvec_record), + 0, SLAB_HWCACHE_ALIGN, NULL); + if (dccp_ackvec_record_slab == NULL) + goto out_destroy_slab; - /* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */ - dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk, - DCCP_SKB_CB(skb)->dccpd_ack_seq, - len, value); return 0; + +out_destroy_slab: + kmem_cache_destroy(dccp_ackvec_slab); + dccp_ackvec_slab = NULL; +out_err: + DCCP_CRIT("Unable to create Ack Vector slab cache"); + return -ENOBUFS; +} + +void dccp_ackvec_exit(void) +{ + if (dccp_ackvec_slab != NULL) { + kmem_cache_destroy(dccp_ackvec_slab); + dccp_ackvec_slab = NULL; + } + if (dccp_ackvec_record_slab != NULL) { + kmem_cache_destroy(dccp_ackvec_record_slab); + dccp_ackvec_record_slab = NULL; + } } diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h index f7dfb5f67b8..3284bfa988c 100644 --- a/net/dccp/ackvec.h +++ b/net/dccp/ackvec.h @@ -3,131 +3,136 @@ /* * net/dccp/ackvec.h * - * An implementation of the DCCP protocol + * An implementation of Ack Vectors for the DCCP protocol + * Copyright (c) 2007 University of Aberdeen, Scotland, UK * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com> - * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ -#include <linux/config.h> +#include <linux/dccp.h> #include <linux/compiler.h> -#include <linux/time.h> +#include <linux/list.h> #include <linux/types.h> -/* Read about the ECN nonce to see why it is 253 */ -#define DCCP_MAX_ACKVEC_LEN 253 +/* + * Ack Vector buffer space is static, in multiples of %DCCP_SINGLE_OPT_MAXLEN, + * the maximum size of a single Ack Vector. Setting %DCCPAV_NUM_ACKVECS to 1 + * will be sufficient for most cases of low Ack Ratios, using a value of 2 gives + * more headroom if Ack Ratio is higher or when the sender acknowledges slowly. + * The maximum value is bounded by the u16 types for indices and functions. + */ +#define DCCPAV_NUM_ACKVECS 2 +#define DCCPAV_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * DCCPAV_NUM_ACKVECS) + +/* Estimated minimum average Ack Vector length - used for updating MPS */ +#define DCCPAV_MIN_OPTLEN 16 + +/* Threshold for coping with large bursts of losses */ +#define DCCPAV_BURST_THRESH (DCCPAV_MAX_ACKVEC_LEN / 8) -#define DCCP_ACKVEC_STATE_RECEIVED 0 -#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6) -#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6) +enum dccp_ackvec_states { + DCCPAV_RECEIVED = 0x00, + DCCPAV_ECN_MARKED = 0x40, + DCCPAV_RESERVED = 0x80, + DCCPAV_NOT_RECEIVED = 0xC0 +}; +#define DCCPAV_MAX_RUNLEN 0x3F -#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */ -#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */ +static inline u8 dccp_ackvec_runlen(const u8 *cell) +{ + return *cell & DCCPAV_MAX_RUNLEN; +} + +static inline u8 dccp_ackvec_state(const u8 *cell) +{ + return *cell & ~DCCPAV_MAX_RUNLEN; +} -/** struct dccp_ackvec - ack vector +/** + * struct dccp_ackvec - Ack Vector main data structure * - * This data structure is the one defined in the DCCP draft - * Appendix A. + * This implements a fixed-size circular buffer within an array and is largely + * based on Appendix A of RFC 4340. * - * @dccpav_buf_head - circular buffer head - * @dccpav_buf_tail - circular buffer tail - * @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the - * buffer (i.e. %dccpav_buf_head) - * @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked - * by the buffer with State 0 + * @av_buf: circular buffer storage area + * @av_buf_head: head index; begin of live portion in @av_buf + * @av_buf_tail: tail index; first index _after_ the live portion in @av_buf + * @av_buf_ackno: highest seqno of acknowledgeable packet recorded in @av_buf + * @av_tail_ackno: lowest seqno of acknowledgeable packet recorded in @av_buf + * @av_buf_nonce: ECN nonce sums, each covering subsequent segments of up to + * %DCCP_SINGLE_OPT_MAXLEN cells in the live portion of @av_buf + * @av_overflow: if 1 then buf_head == buf_tail indicates buffer wraparound + * @av_records: list of %dccp_ackvec_record (Ack Vectors sent previously) + */ +struct dccp_ackvec { + u8 av_buf[DCCPAV_MAX_ACKVEC_LEN]; + u16 av_buf_head; + u16 av_buf_tail; + u64 av_buf_ackno:48; + u64 av_tail_ackno:48; + bool av_buf_nonce[DCCPAV_NUM_ACKVECS]; + u8 av_overflow:1; + struct list_head av_records; +}; + +/** + * struct dccp_ackvec_record - Records information about sent Ack Vectors * - * Additionally, the HC-Receiver must keep some information about the - * Ack Vectors it has recently sent. For each packet sent carrying an - * Ack Vector, it remembers four variables: + * These list entries define the additional information which the HC-Receiver + * keeps about recently-sent Ack Vectors; again refer to RFC 4340, Appendix A. * - * @dccpav_ack_seqno - the Sequence Number used for the packet - * (HC-Receiver seqno) - * @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement. - * @dccpav_ack_ackno - the Acknowledgement Number used for the packet - * (HC-Sender seqno) - * @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0. + * @avr_node: the list node in @av_records + * @avr_ack_seqno: sequence number of the packet the Ack Vector was sent on + * @avr_ack_ackno: the Ack number that this record/Ack Vector refers to + * @avr_ack_ptr: pointer into @av_buf where this record starts + * @avr_ack_runlen: run length of @avr_ack_ptr at the time of sending + * @avr_ack_nonce: the sum of @av_buf_nonce's at the time this record was sent * - * @dccpav_buf_len - circular buffer length - * @dccpav_time - the time in usecs - * @dccpav_buf - circular buffer of acknowledgeable packets + * The list as a whole is sorted in descending order by @avr_ack_seqno. */ -struct dccp_ackvec { - u64 dccpav_buf_ackno; - u64 dccpav_ack_seqno; - u64 dccpav_ack_ackno; - struct timeval dccpav_time; - u8 dccpav_buf_head; - u8 dccpav_buf_tail; - u8 dccpav_ack_ptr; - u8 dccpav_sent_len; - u8 dccpav_vec_len; - u8 dccpav_buf_len; - u8 dccpav_buf_nonce; - u8 dccpav_ack_nonce; - u8 dccpav_buf[0]; +struct dccp_ackvec_record { + struct list_head avr_node; + u64 avr_ack_seqno:48; + u64 avr_ack_ackno:48; + u16 avr_ack_ptr; + u8 avr_ack_runlen; + u8 avr_ack_nonce:1; }; -struct sock; -struct sk_buff; - -#ifdef CONFIG_IP_DCCP_ACKVEC -extern struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len, - const gfp_t priority); -extern void dccp_ackvec_free(struct dccp_ackvec *av); - -extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk, - const u64 ackno, const u8 state); +int dccp_ackvec_init(void); +void dccp_ackvec_exit(void); -extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, - struct sock *sk, const u64 ackno); -extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb, - const u8 opt, const u8 *value, const u8 len); +struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority); +void dccp_ackvec_free(struct dccp_ackvec *av); -extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb); +void dccp_ackvec_input(struct dccp_ackvec *av, struct sk_buff *skb); +int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 sum); +void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno); +u16 dccp_ackvec_buflen(const struct dccp_ackvec *av); -static inline int dccp_ackvec_pending(const struct dccp_ackvec *av) -{ - return av->dccpav_sent_len != av->dccpav_vec_len; -} -#else /* CONFIG_IP_DCCP_ACKVEC */ -static inline struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len, - const gfp_t priority) +static inline bool dccp_ackvec_is_empty(const struct dccp_ackvec *av) { - return NULL; + return av->av_overflow == 0 && av->av_buf_head == av->av_buf_tail; } -static inline void dccp_ackvec_free(struct dccp_ackvec *av) -{ -} - -static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk, - const u64 ackno, const u8 state) -{ - return -1; -} - -static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, - struct sock *sk, const u64 ackno) -{ -} - -static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb, - const u8 opt, const u8 *value, const u8 len) -{ - return -1; -} - -static inline int dccp_insert_option_ackvec(const struct sock *sk, - const struct sk_buff *skb) -{ - return -1; -} +/** + * struct dccp_ackvec_parsed - Record offsets of Ack Vectors in skb + * @vec: start of vector (offset into skb) + * @len: length of @vec + * @nonce: whether @vec had an ECN nonce of 0 or 1 + * @node: FIFO - arranged in descending order of ack_ackno + * + * This structure is used by CCIDs to access Ack Vectors in a received skb. + */ +struct dccp_ackvec_parsed { + u8 *vec, + len, + nonce:1; + struct list_head node; +}; -static inline int dccp_ackvec_pending(const struct dccp_ackvec *av) -{ - return 0; -} -#endif /* CONFIG_IP_DCCP_ACKVEC */ +int dccp_ackvec_parsed_add(struct list_head *head, u8 *vec, u8 len, u8 nonce); +void dccp_ackvec_parsed_cleanup(struct list_head *parsed_chunks); #endif /* _ACKVEC_H */ diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c index 9d8fc0e289e..597557254dd 100644 --- a/net/dccp/ccid.c +++ b/net/dccp/ccid.c @@ -11,129 +11,213 @@ * published by the Free Software Foundation. */ +#include <linux/slab.h> + #include "ccid.h" +#include "ccids/lib/tfrc.h" -static struct ccid *ccids[CCID_MAX]; -#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT) -static atomic_t ccids_lockct = ATOMIC_INIT(0); -static DEFINE_SPINLOCK(ccids_lock); +static struct ccid_operations *ccids[] = { + &ccid2_ops, +#ifdef CONFIG_IP_DCCP_CCID3 + &ccid3_ops, +#endif +}; -/* - * The strategy is: modifications ccids vector are short, do not sleep and - * veeery rare, but read access should be free of any exclusive locks. - */ -static void ccids_write_lock(void) +static struct ccid_operations *ccid_by_number(const u8 id) { - spin_lock(&ccids_lock); - while (atomic_read(&ccids_lockct) != 0) { - spin_unlock(&ccids_lock); - yield(); - spin_lock(&ccids_lock); - } + int i; + + for (i = 0; i < ARRAY_SIZE(ccids); i++) + if (ccids[i]->ccid_id == id) + return ccids[i]; + return NULL; } -static inline void ccids_write_unlock(void) +/* check that up to @array_len members in @ccid_array are supported */ +bool ccid_support_check(u8 const *ccid_array, u8 array_len) { - spin_unlock(&ccids_lock); + while (array_len > 0) + if (ccid_by_number(ccid_array[--array_len]) == NULL) + return false; + return true; } -static inline void ccids_read_lock(void) +/** + * ccid_get_builtin_ccids - Populate a list of built-in CCIDs + * @ccid_array: pointer to copy into + * @array_len: value to return length into + * + * This function allocates memory - caller must see that it is freed after use. + */ +int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len) { - atomic_inc(&ccids_lockct); - spin_unlock_wait(&ccids_lock); + *ccid_array = kmalloc(ARRAY_SIZE(ccids), gfp_any()); + if (*ccid_array == NULL) + return -ENOBUFS; + + for (*array_len = 0; *array_len < ARRAY_SIZE(ccids); *array_len += 1) + (*ccid_array)[*array_len] = ccids[*array_len]->ccid_id; + return 0; } -static inline void ccids_read_unlock(void) +int ccid_getsockopt_builtin_ccids(struct sock *sk, int len, + char __user *optval, int __user *optlen) { - atomic_dec(&ccids_lockct); -} + u8 *ccid_array, array_len; + int err = 0; -#else -#define ccids_write_lock() do { } while(0) -#define ccids_write_unlock() do { } while(0) -#define ccids_read_lock() do { } while(0) -#define ccids_read_unlock() do { } while(0) -#endif + if (ccid_get_builtin_ccids(&ccid_array, &array_len)) + return -ENOBUFS; -int ccid_register(struct ccid *ccid) + if (put_user(array_len, optlen)) + err = -EFAULT; + else if (len > 0 && copy_to_user(optval, ccid_array, + len > array_len ? array_len : len)) + err = -EFAULT; + + kfree(ccid_array); + return err; +} + +static struct kmem_cache *ccid_kmem_cache_create(int obj_size, char *slab_name_fmt, const char *fmt,...) { - int err; + struct kmem_cache *slab; + va_list args; - if (ccid->ccid_init == NULL) - return -1; + va_start(args, fmt); + vsnprintf(slab_name_fmt, CCID_SLAB_NAME_LENGTH, fmt, args); + va_end(args); - ccids_write_lock(); - err = -EEXIST; - if (ccids[ccid->ccid_id] == NULL) { - ccids[ccid->ccid_id] = ccid; - err = 0; - } - ccids_write_unlock(); - if (err == 0) - pr_info("CCID: Registered CCID %d (%s)\n", - ccid->ccid_id, ccid->ccid_name); - return err; + slab = kmem_cache_create(slab_name_fmt, sizeof(struct ccid) + obj_size, 0, + SLAB_HWCACHE_ALIGN, NULL); + return slab; } -EXPORT_SYMBOL_GPL(ccid_register); +static void ccid_kmem_cache_destroy(struct kmem_cache *slab) +{ + if (slab != NULL) + kmem_cache_destroy(slab); +} -int ccid_unregister(struct ccid *ccid) +static int ccid_activate(struct ccid_operations *ccid_ops) { - ccids_write_lock(); - ccids[ccid->ccid_id] = NULL; - ccids_write_unlock(); - pr_info("CCID: Unregistered CCID %d (%s)\n", - ccid->ccid_id, ccid->ccid_name); - return 0; + int err = -ENOBUFS; + + ccid_ops->ccid_hc_rx_slab = + ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size, + ccid_ops->ccid_hc_rx_slab_name, + "ccid%u_hc_rx_sock", + ccid_ops->ccid_id); + if (ccid_ops->ccid_hc_rx_slab == NULL) + goto out; + + ccid_ops->ccid_hc_tx_slab = + ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size, + ccid_ops->ccid_hc_tx_slab_name, + "ccid%u_hc_tx_sock", + ccid_ops->ccid_id); + if (ccid_ops->ccid_hc_tx_slab == NULL) + goto out_free_rx_slab; + + pr_info("DCCP: Activated CCID %d (%s)\n", + ccid_ops->ccid_id, ccid_ops->ccid_name); + err = 0; +out: + return err; +out_free_rx_slab: + ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); + ccid_ops->ccid_hc_rx_slab = NULL; + goto out; } -EXPORT_SYMBOL_GPL(ccid_unregister); +static void ccid_deactivate(struct ccid_operations *ccid_ops) +{ + ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab); + ccid_ops->ccid_hc_tx_slab = NULL; + ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); + ccid_ops->ccid_hc_rx_slab = NULL; + + pr_info("DCCP: Deactivated CCID %d (%s)\n", + ccid_ops->ccid_id, ccid_ops->ccid_name); +} -struct ccid *ccid_init(unsigned char id, struct sock *sk) +struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx) { - struct ccid *ccid; + struct ccid_operations *ccid_ops = ccid_by_number(id); + struct ccid *ccid = NULL; -#ifdef CONFIG_KMOD - if (ccids[id] == NULL) - request_module("net-dccp-ccid-%d", id); -#endif - ccids_read_lock(); + if (ccid_ops == NULL) + goto out; - ccid = ccids[id]; + ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab : + ccid_ops->ccid_hc_tx_slab, gfp_any()); if (ccid == NULL) goto out; - - if (!try_module_get(ccid->ccid_owner)) - goto out_err; - - if (ccid->ccid_init(sk) != 0) - goto out_module_put; + ccid->ccid_ops = ccid_ops; + if (rx) { + memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size); + if (ccid->ccid_ops->ccid_hc_rx_init != NULL && + ccid->ccid_ops->ccid_hc_rx_init(ccid, sk) != 0) + goto out_free_ccid; + } else { + memset(ccid + 1, 0, ccid_ops->ccid_hc_tx_obj_size); + if (ccid->ccid_ops->ccid_hc_tx_init != NULL && + ccid->ccid_ops->ccid_hc_tx_init(ccid, sk) != 0) + goto out_free_ccid; + } out: - ccids_read_unlock(); return ccid; -out_module_put: - module_put(ccid->ccid_owner); -out_err: +out_free_ccid: + kmem_cache_free(rx ? ccid_ops->ccid_hc_rx_slab : + ccid_ops->ccid_hc_tx_slab, ccid); ccid = NULL; goto out; } -EXPORT_SYMBOL_GPL(ccid_init); +void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk) +{ + if (ccid != NULL) { + if (ccid->ccid_ops->ccid_hc_rx_exit != NULL) + ccid->ccid_ops->ccid_hc_rx_exit(sk); + kmem_cache_free(ccid->ccid_ops->ccid_hc_rx_slab, ccid); + } +} -void ccid_exit(struct ccid *ccid, struct sock *sk) +void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk) { - if (ccid == NULL) - return; + if (ccid != NULL) { + if (ccid->ccid_ops->ccid_hc_tx_exit != NULL) + ccid->ccid_ops->ccid_hc_tx_exit(sk); + kmem_cache_free(ccid->ccid_ops->ccid_hc_tx_slab, ccid); + } +} + +int __init ccid_initialize_builtins(void) +{ + int i, err = tfrc_lib_init(); - ccids_read_lock(); + if (err) + return err; - if (ccids[ccid->ccid_id] != NULL) { - if (ccid->ccid_exit != NULL) - ccid->ccid_exit(sk); - module_put(ccid->ccid_owner); + for (i = 0; i < ARRAY_SIZE(ccids); i++) { + err = ccid_activate(ccids[i]); + if (err) + goto unwind_registrations; } + return 0; - ccids_read_unlock(); +unwind_registrations: + while(--i >= 0) + ccid_deactivate(ccids[i]); + tfrc_lib_exit(); + return err; } -EXPORT_SYMBOL_GPL(ccid_exit); +void ccid_cleanup_builtins(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ccids); i++) + ccid_deactivate(ccids[i]); + tfrc_lib_exit(); +} diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h index de681c6ad08..6eb837a47b5 100644 --- a/net/dccp/ccid.h +++ b/net/dccp/ccid.h @@ -19,40 +19,61 @@ #include <linux/list.h> #include <linux/module.h> -#define CCID_MAX 255 +/* maximum value for a CCID (RFC 4340, 19.5) */ +#define CCID_MAX 255 +#define CCID_SLAB_NAME_LENGTH 32 struct tcp_info; -struct ccid { - unsigned char ccid_id; - const char *ccid_name; - struct module *ccid_owner; - int (*ccid_init)(struct sock *sk); - void (*ccid_exit)(struct sock *sk); - int (*ccid_hc_rx_init)(struct sock *sk); - int (*ccid_hc_tx_init)(struct sock *sk); +/** + * struct ccid_operations - Interface to Congestion-Control Infrastructure + * + * @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.) + * @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled) + * @ccid_name: alphabetical identifier string for @ccid_id + * @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection + * @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket + * + * @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup) + * @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction) + * @ccid_hc_rx_packet_recv: implements the HC-receiver side + * @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options + * @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options + * @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender + * @ccid_hc_tx_send_packet: implements the sending part of the HC-sender + * @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender + * @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender + * @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender + */ +struct ccid_operations { + unsigned char ccid_id; + __u32 ccid_ccmps; + const char *ccid_name; + struct kmem_cache *ccid_hc_rx_slab, + *ccid_hc_tx_slab; + char ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH]; + char ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH]; + __u32 ccid_hc_rx_obj_size, + ccid_hc_tx_obj_size; + /* Interface Routines */ + int (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk); + int (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk); void (*ccid_hc_rx_exit)(struct sock *sk); void (*ccid_hc_tx_exit)(struct sock *sk); void (*ccid_hc_rx_packet_recv)(struct sock *sk, struct sk_buff *skb); - int (*ccid_hc_rx_parse_options)(struct sock *sk, - unsigned char option, - unsigned char len, u16 idx, - unsigned char* value); - void (*ccid_hc_rx_insert_options)(struct sock *sk, - struct sk_buff *skb); - void (*ccid_hc_tx_insert_options)(struct sock *sk, + int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt, + u8 opt, u8 *val, u8 len); + int (*ccid_hc_rx_insert_options)(struct sock *sk, struct sk_buff *skb); void (*ccid_hc_tx_packet_recv)(struct sock *sk, struct sk_buff *skb); - int (*ccid_hc_tx_parse_options)(struct sock *sk, - unsigned char option, - unsigned char len, u16 idx, - unsigned char* value); + int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt, + u8 opt, u8 *val, u8 len); int (*ccid_hc_tx_send_packet)(struct sock *sk, - struct sk_buff *skb, int len); - void (*ccid_hc_tx_packet_sent)(struct sock *sk, int more, - int len); + struct sk_buff *skb); + void (*ccid_hc_tx_packet_sent)(struct sock *sk, + unsigned int len); void (*ccid_hc_rx_get_info)(struct sock *sk, struct tcp_info *info); void (*ccid_hc_tx_get_info)(struct sock *sk, @@ -67,126 +88,157 @@ struct ccid { int __user *optlen); }; -extern int ccid_register(struct ccid *ccid); -extern int ccid_unregister(struct ccid *ccid); +extern struct ccid_operations ccid2_ops; +#ifdef CONFIG_IP_DCCP_CCID3 +extern struct ccid_operations ccid3_ops; +#endif -extern struct ccid *ccid_init(unsigned char id, struct sock *sk); -extern void ccid_exit(struct ccid *ccid, struct sock *sk); +int ccid_initialize_builtins(void); +void ccid_cleanup_builtins(void); -static inline void __ccid_get(struct ccid *ccid) -{ - __module_get(ccid->ccid_owner); -} +struct ccid { + struct ccid_operations *ccid_ops; + char ccid_priv[0]; +}; -static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk, - struct sk_buff *skb, int len) +static inline void *ccid_priv(const struct ccid *ccid) { - int rc = 0; - if (ccid->ccid_hc_tx_send_packet != NULL) - rc = ccid->ccid_hc_tx_send_packet(sk, skb, len); - return rc; + return (void *)ccid->ccid_priv; } -static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk, - int more, int len) +bool ccid_support_check(u8 const *ccid_array, u8 array_len); +int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len); +int ccid_getsockopt_builtin_ccids(struct sock *sk, int len, + char __user *, int __user *); + +struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx); + +static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp) { - if (ccid->ccid_hc_tx_packet_sent != NULL) - ccid->ccid_hc_tx_packet_sent(sk, more, len); + struct ccid *ccid = dp->dccps_hc_rx_ccid; + + if (ccid == NULL || ccid->ccid_ops == NULL) + return -1; + return ccid->ccid_ops->ccid_id; } -static inline int ccid_hc_rx_init(struct ccid *ccid, struct sock *sk) +static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp) { - int rc = 0; - if (ccid->ccid_hc_rx_init != NULL) - rc = ccid->ccid_hc_rx_init(sk); - return rc; + struct ccid *ccid = dp->dccps_hc_tx_ccid; + + if (ccid == NULL || ccid->ccid_ops == NULL) + return -1; + return ccid->ccid_ops->ccid_id; } -static inline int ccid_hc_tx_init(struct ccid *ccid, struct sock *sk) +void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk); +void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk); + +/* + * Congestion control of queued data packets via CCID decision. + * + * The TX CCID performs its congestion-control by indicating whether and when a + * queued packet may be sent, using the return code of ccid_hc_tx_send_packet(). + * The following modes are supported via the symbolic constants below: + * - timer-based pacing (CCID returns a delay value in milliseconds); + * - autonomous dequeueing (CCID internally schedules dccps_xmitlet). + */ + +enum ccid_dequeueing_decision { + CCID_PACKET_SEND_AT_ONCE = 0x00000, /* "green light": no delay */ + CCID_PACKET_DELAY_MAX = 0x0FFFF, /* maximum delay in msecs */ + CCID_PACKET_DELAY = 0x10000, /* CCID msec-delay mode */ + CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000, /* CCID autonomous mode */ + CCID_PACKET_ERR = 0xF0000, /* error condition */ +}; + +static inline int ccid_packet_dequeue_eval(const int return_code) { - int rc = 0; - if (ccid->ccid_hc_tx_init != NULL) - rc = ccid->ccid_hc_tx_init(sk); - return rc; + if (return_code < 0) + return CCID_PACKET_ERR; + if (return_code == 0) + return CCID_PACKET_SEND_AT_ONCE; + if (return_code <= CCID_PACKET_DELAY_MAX) + return CCID_PACKET_DELAY; + return return_code; } -static inline void ccid_hc_rx_exit(struct ccid *ccid, struct sock *sk) +static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) { - if (ccid != NULL && ccid->ccid_hc_rx_exit != NULL && - dccp_sk(sk)->dccps_hc_rx_ccid_private != NULL) - ccid->ccid_hc_rx_exit(sk); + if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL) + return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb); + return CCID_PACKET_SEND_AT_ONCE; } -static inline void ccid_hc_tx_exit(struct ccid *ccid, struct sock *sk) +static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk, + unsigned int len) { - if (ccid != NULL && ccid->ccid_hc_tx_exit != NULL && - dccp_sk(sk)->dccps_hc_tx_ccid_private != NULL) - ccid->ccid_hc_tx_exit(sk); + if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL) + ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len); } static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk, struct sk_buff *skb) { - if (ccid->ccid_hc_rx_packet_recv != NULL) - ccid->ccid_hc_rx_packet_recv(sk, skb); + if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL) + ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb); } static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk, struct sk_buff *skb) { - if (ccid->ccid_hc_tx_packet_recv != NULL) - ccid->ccid_hc_tx_packet_recv(sk, skb); + if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL) + ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb); } +/** + * ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver + * @pkt: type of packet that @opt appears on (RFC 4340, 5.1) + * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3) + * @val: value of @opt + * @len: length of @val in bytes + */ static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk, - unsigned char option, - unsigned char len, u16 idx, - unsigned char* value) + u8 pkt, u8 opt, u8 *val, u8 len) { - int rc = 0; - if (ccid->ccid_hc_tx_parse_options != NULL) - rc = ccid->ccid_hc_tx_parse_options(sk, option, len, idx, - value); - return rc; + if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL) + return 0; + return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len); } +/** + * ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender + * Arguments are analogous to ccid_hc_tx_parse_options() + */ static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk, - unsigned char option, - unsigned char len, u16 idx, - unsigned char* value) -{ - int rc = 0; - if (ccid->ccid_hc_rx_parse_options != NULL) - rc = ccid->ccid_hc_rx_parse_options(sk, option, len, idx, value); - return rc; -} - -static inline void ccid_hc_tx_insert_options(struct ccid *ccid, struct sock *sk, - struct sk_buff *skb) + u8 pkt, u8 opt, u8 *val, u8 len) { - if (ccid->ccid_hc_tx_insert_options != NULL) - ccid->ccid_hc_tx_insert_options(sk, skb); + if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL) + return 0; + return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len); } -static inline void ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk, - struct sk_buff *skb) +static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk, + struct sk_buff *skb) { - if (ccid->ccid_hc_rx_insert_options != NULL) - ccid->ccid_hc_rx_insert_options(sk, skb); + if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL) + return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb); + return 0; } static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk, struct tcp_info *info) { - if (ccid->ccid_hc_rx_get_info != NULL) - ccid->ccid_hc_rx_get_info(sk, info); + if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL) + ccid->ccid_ops->ccid_hc_rx_get_info(sk, info); } static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk, struct tcp_info *info) { - if (ccid->ccid_hc_tx_get_info != NULL) - ccid->ccid_hc_tx_get_info(sk, info); + if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL) + ccid->ccid_ops->ccid_hc_tx_get_info(sk, info); } static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk, @@ -194,8 +246,8 @@ static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk, u32 __user *optval, int __user *optlen) { int rc = -ENOPROTOOPT; - if (ccid->ccid_hc_rx_getsockopt != NULL) - rc = ccid->ccid_hc_rx_getsockopt(sk, optname, len, + if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL) + rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len, optval, optlen); return rc; } @@ -205,8 +257,8 @@ static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk, u32 __user *optval, int __user *optlen) { int rc = -ENOPROTOOPT; - if (ccid->ccid_hc_tx_getsockopt != NULL) - rc = ccid->ccid_hc_tx_getsockopt(sk, optname, len, + if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL) + rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len, optval, optlen); return rc; } diff --git a/net/dccp/ccids/Kconfig b/net/dccp/ccids/Kconfig index 7684d83946a..8ba3fc9d6d1 100644 --- a/net/dccp/ccids/Kconfig +++ b/net/dccp/ccids/Kconfig @@ -1,29 +1,54 @@ -menu "DCCP CCIDs Configuration (EXPERIMENTAL)" - depends on IP_DCCP && EXPERIMENTAL +menu "DCCP CCIDs Configuration" + +config IP_DCCP_CCID2_DEBUG + bool "CCID-2 debugging messages" + ---help--- + Enable CCID-2 specific debugging messages. + + The debugging output can additionally be toggled by setting the + ccid2_debug parameter to 0 or 1. + + If in doubt, say N. config IP_DCCP_CCID3 - tristate "CCID3 (TFRC) (EXPERIMENTAL)" - depends on IP_DCCP + bool "CCID-3 (TCP-Friendly)" + def_bool y if (IP_DCCP = y || IP_DCCP = m) ---help--- - CCID 3 denotes TCP-Friendly Rate Control (TFRC), an equation-based + CCID-3 denotes TCP-Friendly Rate Control (TFRC), an equation-based rate-controlled congestion control mechanism. TFRC is designed to be reasonably fair when competing for bandwidth with TCP-like flows, where a flow is "reasonably fair" if its sending rate is generally within a factor of two of the sending rate of a TCP flow under the same conditions. However, TFRC has a much lower variation of - throughput over time compared with TCP, which makes CCID 3 more - suitable than CCID 2 for applications such streaming media where a + throughput over time compared with TCP, which makes CCID-3 more + suitable than CCID-2 for applications such streaming media where a relatively smooth sending rate is of importance. - CCID 3 is further described in [CCID 3 PROFILE]. The TFRC - congestion control algorithms were initially described in RFC 3448. + CCID-3 is further described in RFC 4342, + http://www.ietf.org/rfc/rfc4342.txt - This text was extracted from draft-ietf-dccp-spec-11.txt. - - If in doubt, say M. + The TFRC congestion control algorithms were initially described in + RFC 5348. -config IP_DCCP_TFRC_LIB + This text was extracted from RFC 4340 (sec. 10.2), + http://www.ietf.org/rfc/rfc4340.txt + + If in doubt, say N. + +config IP_DCCP_CCID3_DEBUG + bool "CCID-3 debugging messages" depends on IP_DCCP_CCID3 - def_tristate IP_DCCP_CCID3 + ---help--- + Enable CCID-3 specific debugging messages. + + The debugging output can additionally be toggled by setting the + ccid3_debug parameter to 0 or 1. + + If in doubt, say N. + +config IP_DCCP_TFRC_LIB + def_bool y if IP_DCCP_CCID3 +config IP_DCCP_TFRC_DEBUG + def_bool y if IP_DCCP_CCID3_DEBUG endmenu diff --git a/net/dccp/ccids/Makefile b/net/dccp/ccids/Makefile deleted file mode 100644 index 956f79f5074..00000000000 --- a/net/dccp/ccids/Makefile +++ /dev/null @@ -1,5 +0,0 @@ -obj-$(CONFIG_IP_DCCP_CCID3) += dccp_ccid3.o - -dccp_ccid3-y := ccid3.o - -obj-y += lib/ diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c new file mode 100644 index 00000000000..f053198e730 --- /dev/null +++ b/net/dccp/ccids/ccid2.c @@ -0,0 +1,784 @@ +/* + * Copyright (c) 2005, 2006 Andrea Bittau <a.bittau@cs.ucl.ac.uk> + * + * Changes to meet Linux coding standards, and DCCP infrastructure fixes. + * + * Copyright (c) 2006 Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* + * This implementation should follow RFC 4341 + */ +#include <linux/slab.h> +#include "../feat.h" +#include "ccid2.h" + + +#ifdef CONFIG_IP_DCCP_CCID2_DEBUG +static bool ccid2_debug; +#define ccid2_pr_debug(format, a...) DCCP_PR_DEBUG(ccid2_debug, format, ##a) +#else +#define ccid2_pr_debug(format, a...) +#endif + +static int ccid2_hc_tx_alloc_seq(struct ccid2_hc_tx_sock *hc) +{ + struct ccid2_seq *seqp; + int i; + + /* check if we have space to preserve the pointer to the buffer */ + if (hc->tx_seqbufc >= (sizeof(hc->tx_seqbuf) / + sizeof(struct ccid2_seq *))) + return -ENOMEM; + + /* allocate buffer and initialize linked list */ + seqp = kmalloc(CCID2_SEQBUF_LEN * sizeof(struct ccid2_seq), gfp_any()); + if (seqp == NULL) + return -ENOMEM; + + for (i = 0; i < (CCID2_SEQBUF_LEN - 1); i++) { + seqp[i].ccid2s_next = &seqp[i + 1]; + seqp[i + 1].ccid2s_prev = &seqp[i]; + } + seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = seqp; + seqp->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1]; + + /* This is the first allocation. Initiate the head and tail. */ + if (hc->tx_seqbufc == 0) + hc->tx_seqh = hc->tx_seqt = seqp; + else { + /* link the existing list with the one we just created */ + hc->tx_seqh->ccid2s_next = seqp; + seqp->ccid2s_prev = hc->tx_seqh; + + hc->tx_seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1]; + seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hc->tx_seqt; + } + + /* store the original pointer to the buffer so we can free it */ + hc->tx_seqbuf[hc->tx_seqbufc] = seqp; + hc->tx_seqbufc++; + + return 0; +} + +static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) +{ + if (ccid2_cwnd_network_limited(ccid2_hc_tx_sk(sk))) + return CCID_PACKET_WILL_DEQUEUE_LATER; + return CCID_PACKET_SEND_AT_ONCE; +} + +static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val) +{ + u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->tx_cwnd, 2); + + /* + * Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from + * RFC 4341, 6.1.2. We ignore the statement that Ack Ratio 2 is always + * acceptable since this causes starvation/deadlock whenever cwnd < 2. + * The same problem arises when Ack Ratio is 0 (ie. Ack Ratio disabled). + */ + if (val == 0 || val > max_ratio) { + DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio); + val = max_ratio; + } + dccp_feat_signal_nn_change(sk, DCCPF_ACK_RATIO, + min_t(u32, val, DCCPF_ACK_RATIO_MAX)); +} + +static void ccid2_check_l_ack_ratio(struct sock *sk) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + + /* + * After a loss, idle period, application limited period, or RTO we + * need to check that the ack ratio is still less than the congestion + * window. Otherwise, we will send an entire congestion window of + * packets and got no response because we haven't sent ack ratio + * packets yet. + * If the ack ratio does need to be reduced, we reduce it to half of + * the congestion window (or 1 if that's zero) instead of to the + * congestion window. This prevents problems if one ack is lost. + */ + if (dccp_feat_nn_get(sk, DCCPF_ACK_RATIO) > hc->tx_cwnd) + ccid2_change_l_ack_ratio(sk, hc->tx_cwnd/2 ? : 1U); +} + +static void ccid2_change_l_seq_window(struct sock *sk, u64 val) +{ + dccp_feat_signal_nn_change(sk, DCCPF_SEQUENCE_WINDOW, + clamp_val(val, DCCPF_SEQ_WMIN, + DCCPF_SEQ_WMAX)); +} + +static void ccid2_hc_tx_rto_expire(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + const bool sender_was_blocked = ccid2_cwnd_network_limited(hc); + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + sk_reset_timer(sk, &hc->tx_rtotimer, jiffies + HZ / 5); + goto out; + } + + ccid2_pr_debug("RTO_EXPIRE\n"); + + /* back-off timer */ + hc->tx_rto <<= 1; + if (hc->tx_rto > DCCP_RTO_MAX) + hc->tx_rto = DCCP_RTO_MAX; + + /* adjust pipe, cwnd etc */ + hc->tx_ssthresh = hc->tx_cwnd / 2; + if (hc->tx_ssthresh < 2) + hc->tx_ssthresh = 2; + hc->tx_cwnd = 1; + hc->tx_pipe = 0; + + /* clear state about stuff we sent */ + hc->tx_seqt = hc->tx_seqh; + hc->tx_packets_acked = 0; + + /* clear ack ratio state. */ + hc->tx_rpseq = 0; + hc->tx_rpdupack = -1; + ccid2_change_l_ack_ratio(sk, 1); + + /* if we were blocked before, we may now send cwnd=1 packet */ + if (sender_was_blocked) + tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet); + /* restart backed-off timer */ + sk_reset_timer(sk, &hc->tx_rtotimer, jiffies + hc->tx_rto); +out: + bh_unlock_sock(sk); + sock_put(sk); +} + +/* + * Congestion window validation (RFC 2861). + */ +static bool ccid2_do_cwv = true; +module_param(ccid2_do_cwv, bool, 0644); +MODULE_PARM_DESC(ccid2_do_cwv, "Perform RFC2861 Congestion Window Validation"); + +/** + * ccid2_update_used_window - Track how much of cwnd is actually used + * This is done in addition to CWV. The sender needs to have an idea of how many + * packets may be in flight, to set the local Sequence Window value accordingly + * (RFC 4340, 7.5.2). The CWV mechanism is exploited to keep track of the + * maximum-used window. We use an EWMA low-pass filter to filter out noise. + */ +static void ccid2_update_used_window(struct ccid2_hc_tx_sock *hc, u32 new_wnd) +{ + hc->tx_expected_wnd = (3 * hc->tx_expected_wnd + new_wnd) / 4; +} + +/* This borrows the code of tcp_cwnd_application_limited() */ +static void ccid2_cwnd_application_limited(struct sock *sk, const u32 now) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + /* don't reduce cwnd below the initial window (IW) */ + u32 init_win = rfc3390_bytes_to_packets(dccp_sk(sk)->dccps_mss_cache), + win_used = max(hc->tx_cwnd_used, init_win); + + if (win_used < hc->tx_cwnd) { + hc->tx_ssthresh = max(hc->tx_ssthresh, + (hc->tx_cwnd >> 1) + (hc->tx_cwnd >> 2)); + hc->tx_cwnd = (hc->tx_cwnd + win_used) >> 1; + } + hc->tx_cwnd_used = 0; + hc->tx_cwnd_stamp = now; + + ccid2_check_l_ack_ratio(sk); +} + +/* This borrows the code of tcp_cwnd_restart() */ +static void ccid2_cwnd_restart(struct sock *sk, const u32 now) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + u32 cwnd = hc->tx_cwnd, restart_cwnd, + iwnd = rfc3390_bytes_to_packets(dccp_sk(sk)->dccps_mss_cache); + + hc->tx_ssthresh = max(hc->tx_ssthresh, (cwnd >> 1) + (cwnd >> 2)); + + /* don't reduce cwnd below the initial window (IW) */ + restart_cwnd = min(cwnd, iwnd); + cwnd >>= (now - hc->tx_lsndtime) / hc->tx_rto; + hc->tx_cwnd = max(cwnd, restart_cwnd); + + hc->tx_cwnd_stamp = now; + hc->tx_cwnd_used = 0; + + ccid2_check_l_ack_ratio(sk); +} + +static void ccid2_hc_tx_packet_sent(struct sock *sk, unsigned int len) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + const u32 now = ccid2_time_stamp; + struct ccid2_seq *next; + + /* slow-start after idle periods (RFC 2581, RFC 2861) */ + if (ccid2_do_cwv && !hc->tx_pipe && + (s32)(now - hc->tx_lsndtime) >= hc->tx_rto) + ccid2_cwnd_restart(sk, now); + + hc->tx_lsndtime = now; + hc->tx_pipe += 1; + + /* see whether cwnd was fully used (RFC 2861), update expected window */ + if (ccid2_cwnd_network_limited(hc)) { + ccid2_update_used_window(hc, hc->tx_cwnd); + hc->tx_cwnd_used = 0; + hc->tx_cwnd_stamp = now; + } else { + if (hc->tx_pipe > hc->tx_cwnd_used) + hc->tx_cwnd_used = hc->tx_pipe; + + ccid2_update_used_window(hc, hc->tx_cwnd_used); + + if (ccid2_do_cwv && (s32)(now - hc->tx_cwnd_stamp) >= hc->tx_rto) + ccid2_cwnd_application_limited(sk, now); + } + + hc->tx_seqh->ccid2s_seq = dp->dccps_gss; + hc->tx_seqh->ccid2s_acked = 0; + hc->tx_seqh->ccid2s_sent = now; + + next = hc->tx_seqh->ccid2s_next; + /* check if we need to alloc more space */ + if (next == hc->tx_seqt) { + if (ccid2_hc_tx_alloc_seq(hc)) { + DCCP_CRIT("packet history - out of memory!"); + /* FIXME: find a more graceful way to bail out */ + return; + } + next = hc->tx_seqh->ccid2s_next; + BUG_ON(next == hc->tx_seqt); + } + hc->tx_seqh = next; + + ccid2_pr_debug("cwnd=%d pipe=%d\n", hc->tx_cwnd, hc->tx_pipe); + + /* + * FIXME: The code below is broken and the variables have been removed + * from the socket struct. The `ackloss' variable was always set to 0, + * and with arsent there are several problems: + * (i) it doesn't just count the number of Acks, but all sent packets; + * (ii) it is expressed in # of packets, not # of windows, so the + * comparison below uses the wrong formula: Appendix A of RFC 4341 + * comes up with the number K = cwnd / (R^2 - R) of consecutive windows + * of data with no lost or marked Ack packets. If arsent were the # of + * consecutive Acks received without loss, then Ack Ratio needs to be + * decreased by 1 when + * arsent >= K * cwnd / R = cwnd^2 / (R^3 - R^2) + * where cwnd / R is the number of Acks received per window of data + * (cf. RFC 4341, App. A). The problems are that + * - arsent counts other packets as well; + * - the comparison uses a formula different from RFC 4341; + * - computing a cubic/quadratic equation each time is too complicated. + * Hence a different algorithm is needed. + */ +#if 0 + /* Ack Ratio. Need to maintain a concept of how many windows we sent */ + hc->tx_arsent++; + /* We had an ack loss in this window... */ + if (hc->tx_ackloss) { + if (hc->tx_arsent >= hc->tx_cwnd) { + hc->tx_arsent = 0; + hc->tx_ackloss = 0; + } + } else { + /* No acks lost up to now... */ + /* decrease ack ratio if enough packets were sent */ + if (dp->dccps_l_ack_ratio > 1) { + /* XXX don't calculate denominator each time */ + int denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio - + dp->dccps_l_ack_ratio; + + denom = hc->tx_cwnd * hc->tx_cwnd / denom; + + if (hc->tx_arsent >= denom) { + ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1); + hc->tx_arsent = 0; + } + } else { + /* we can't increase ack ratio further [1] */ + hc->tx_arsent = 0; /* or maybe set it to cwnd*/ + } + } +#endif + + sk_reset_timer(sk, &hc->tx_rtotimer, jiffies + hc->tx_rto); + +#ifdef CONFIG_IP_DCCP_CCID2_DEBUG + do { + struct ccid2_seq *seqp = hc->tx_seqt; + + while (seqp != hc->tx_seqh) { + ccid2_pr_debug("out seq=%llu acked=%d time=%u\n", + (unsigned long long)seqp->ccid2s_seq, + seqp->ccid2s_acked, seqp->ccid2s_sent); + seqp = seqp->ccid2s_next; + } + } while (0); + ccid2_pr_debug("=========\n"); +#endif +} + +/** + * ccid2_rtt_estimator - Sample RTT and compute RTO using RFC2988 algorithm + * This code is almost identical with TCP's tcp_rtt_estimator(), since + * - it has a higher sampling frequency (recommended by RFC 1323), + * - the RTO does not collapse into RTT due to RTTVAR going towards zero, + * - it is simple (cf. more complex proposals such as Eifel timer or research + * which suggests that the gain should be set according to window size), + * - in tests it was found to work well with CCID2 [gerrit]. + */ +static void ccid2_rtt_estimator(struct sock *sk, const long mrtt) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + long m = mrtt ? : 1; + + if (hc->tx_srtt == 0) { + /* First measurement m */ + hc->tx_srtt = m << 3; + hc->tx_mdev = m << 1; + + hc->tx_mdev_max = max(hc->tx_mdev, tcp_rto_min(sk)); + hc->tx_rttvar = hc->tx_mdev_max; + + hc->tx_rtt_seq = dccp_sk(sk)->dccps_gss; + } else { + /* Update scaled SRTT as SRTT += 1/8 * (m - SRTT) */ + m -= (hc->tx_srtt >> 3); + hc->tx_srtt += m; + + /* Similarly, update scaled mdev with regard to |m| */ + if (m < 0) { + m = -m; + m -= (hc->tx_mdev >> 2); + /* + * This neutralises RTO increase when RTT < SRTT - mdev + * (see P. Sarolahti, A. Kuznetsov,"Congestion Control + * in Linux TCP", USENIX 2002, pp. 49-62). + */ + if (m > 0) + m >>= 3; + } else { + m -= (hc->tx_mdev >> 2); + } + hc->tx_mdev += m; + + if (hc->tx_mdev > hc->tx_mdev_max) { + hc->tx_mdev_max = hc->tx_mdev; + if (hc->tx_mdev_max > hc->tx_rttvar) + hc->tx_rttvar = hc->tx_mdev_max; + } + + /* + * Decay RTTVAR at most once per flight, exploiting that + * 1) pipe <= cwnd <= Sequence_Window = W (RFC 4340, 7.5.2) + * 2) AWL = GSS-W+1 <= GAR <= GSS (RFC 4340, 7.5.1) + * GAR is a useful bound for FlightSize = pipe. + * AWL is probably too low here, as it over-estimates pipe. + */ + if (after48(dccp_sk(sk)->dccps_gar, hc->tx_rtt_seq)) { + if (hc->tx_mdev_max < hc->tx_rttvar) + hc->tx_rttvar -= (hc->tx_rttvar - + hc->tx_mdev_max) >> 2; + hc->tx_rtt_seq = dccp_sk(sk)->dccps_gss; + hc->tx_mdev_max = tcp_rto_min(sk); + } + } + + /* + * Set RTO from SRTT and RTTVAR + * As in TCP, 4 * RTTVAR >= TCP_RTO_MIN, giving a minimum RTO of 200 ms. + * This agrees with RFC 4341, 5: + * "Because DCCP does not retransmit data, DCCP does not require + * TCP's recommended minimum timeout of one second". + */ + hc->tx_rto = (hc->tx_srtt >> 3) + hc->tx_rttvar; + + if (hc->tx_rto > DCCP_RTO_MAX) + hc->tx_rto = DCCP_RTO_MAX; +} + +static void ccid2_new_ack(struct sock *sk, struct ccid2_seq *seqp, + unsigned int *maxincr) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + struct dccp_sock *dp = dccp_sk(sk); + int r_seq_used = hc->tx_cwnd / dp->dccps_l_ack_ratio; + + if (hc->tx_cwnd < dp->dccps_l_seq_win && + r_seq_used < dp->dccps_r_seq_win) { + if (hc->tx_cwnd < hc->tx_ssthresh) { + if (*maxincr > 0 && ++hc->tx_packets_acked >= 2) { + hc->tx_cwnd += 1; + *maxincr -= 1; + hc->tx_packets_acked = 0; + } + } else if (++hc->tx_packets_acked >= hc->tx_cwnd) { + hc->tx_cwnd += 1; + hc->tx_packets_acked = 0; + } + } + + /* + * Adjust the local sequence window and the ack ratio to allow about + * 5 times the number of packets in the network (RFC 4340 7.5.2) + */ + if (r_seq_used * CCID2_WIN_CHANGE_FACTOR >= dp->dccps_r_seq_win) + ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio * 2); + else if (r_seq_used * CCID2_WIN_CHANGE_FACTOR < dp->dccps_r_seq_win/2) + ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio / 2 ? : 1U); + + if (hc->tx_cwnd * CCID2_WIN_CHANGE_FACTOR >= dp->dccps_l_seq_win) + ccid2_change_l_seq_window(sk, dp->dccps_l_seq_win * 2); + else if (hc->tx_cwnd * CCID2_WIN_CHANGE_FACTOR < dp->dccps_l_seq_win/2) + ccid2_change_l_seq_window(sk, dp->dccps_l_seq_win / 2); + + /* + * FIXME: RTT is sampled several times per acknowledgment (for each + * entry in the Ack Vector), instead of once per Ack (as in TCP SACK). + * This causes the RTT to be over-estimated, since the older entries + * in the Ack Vector have earlier sending times. + * The cleanest solution is to not use the ccid2s_sent field at all + * and instead use DCCP timestamps: requires changes in other places. + */ + ccid2_rtt_estimator(sk, ccid2_time_stamp - seqp->ccid2s_sent); +} + +static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + + if ((s32)(seqp->ccid2s_sent - hc->tx_last_cong) < 0) { + ccid2_pr_debug("Multiple losses in an RTT---treating as one\n"); + return; + } + + hc->tx_last_cong = ccid2_time_stamp; + + hc->tx_cwnd = hc->tx_cwnd / 2 ? : 1U; + hc->tx_ssthresh = max(hc->tx_cwnd, 2U); + + ccid2_check_l_ack_ratio(sk); +} + +static int ccid2_hc_tx_parse_options(struct sock *sk, u8 packet_type, + u8 option, u8 *optval, u8 optlen) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + + switch (option) { + case DCCPO_ACK_VECTOR_0: + case DCCPO_ACK_VECTOR_1: + return dccp_ackvec_parsed_add(&hc->tx_av_chunks, optval, optlen, + option - DCCPO_ACK_VECTOR_0); + } + return 0; +} + +static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + const bool sender_was_blocked = ccid2_cwnd_network_limited(hc); + struct dccp_ackvec_parsed *avp; + u64 ackno, seqno; + struct ccid2_seq *seqp; + int done = 0; + unsigned int maxincr = 0; + + /* check reverse path congestion */ + seqno = DCCP_SKB_CB(skb)->dccpd_seq; + + /* XXX this whole "algorithm" is broken. Need to fix it to keep track + * of the seqnos of the dupacks so that rpseq and rpdupack are correct + * -sorbo. + */ + /* need to bootstrap */ + if (hc->tx_rpdupack == -1) { + hc->tx_rpdupack = 0; + hc->tx_rpseq = seqno; + } else { + /* check if packet is consecutive */ + if (dccp_delta_seqno(hc->tx_rpseq, seqno) == 1) + hc->tx_rpseq = seqno; + /* it's a later packet */ + else if (after48(seqno, hc->tx_rpseq)) { + hc->tx_rpdupack++; + + /* check if we got enough dupacks */ + if (hc->tx_rpdupack >= NUMDUPACK) { + hc->tx_rpdupack = -1; /* XXX lame */ + hc->tx_rpseq = 0; +#ifdef __CCID2_COPES_GRACEFULLY_WITH_ACK_CONGESTION_CONTROL__ + /* + * FIXME: Ack Congestion Control is broken; in + * the current state instabilities occurred with + * Ack Ratios greater than 1; causing hang-ups + * and long RTO timeouts. This needs to be fixed + * before opening up dynamic changes. -- gerrit + */ + ccid2_change_l_ack_ratio(sk, 2 * dp->dccps_l_ack_ratio); +#endif + } + } + } + + /* check forward path congestion */ + if (dccp_packet_without_ack(skb)) + return; + + /* still didn't send out new data packets */ + if (hc->tx_seqh == hc->tx_seqt) + goto done; + + ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; + if (after48(ackno, hc->tx_high_ack)) + hc->tx_high_ack = ackno; + + seqp = hc->tx_seqt; + while (before48(seqp->ccid2s_seq, ackno)) { + seqp = seqp->ccid2s_next; + if (seqp == hc->tx_seqh) { + seqp = hc->tx_seqh->ccid2s_prev; + break; + } + } + + /* + * In slow-start, cwnd can increase up to a maximum of Ack Ratio/2 + * packets per acknowledgement. Rounding up avoids that cwnd is not + * advanced when Ack Ratio is 1 and gives a slight edge otherwise. + */ + if (hc->tx_cwnd < hc->tx_ssthresh) + maxincr = DIV_ROUND_UP(dp->dccps_l_ack_ratio, 2); + + /* go through all ack vectors */ + list_for_each_entry(avp, &hc->tx_av_chunks, node) { + /* go through this ack vector */ + for (; avp->len--; avp->vec++) { + u64 ackno_end_rl = SUB48(ackno, + dccp_ackvec_runlen(avp->vec)); + + ccid2_pr_debug("ackvec %llu |%u,%u|\n", + (unsigned long long)ackno, + dccp_ackvec_state(avp->vec) >> 6, + dccp_ackvec_runlen(avp->vec)); + /* if the seqno we are analyzing is larger than the + * current ackno, then move towards the tail of our + * seqnos. + */ + while (after48(seqp->ccid2s_seq, ackno)) { + if (seqp == hc->tx_seqt) { + done = 1; + break; + } + seqp = seqp->ccid2s_prev; + } + if (done) + break; + + /* check all seqnos in the range of the vector + * run length + */ + while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) { + const u8 state = dccp_ackvec_state(avp->vec); + + /* new packet received or marked */ + if (state != DCCPAV_NOT_RECEIVED && + !seqp->ccid2s_acked) { + if (state == DCCPAV_ECN_MARKED) + ccid2_congestion_event(sk, + seqp); + else + ccid2_new_ack(sk, seqp, + &maxincr); + + seqp->ccid2s_acked = 1; + ccid2_pr_debug("Got ack for %llu\n", + (unsigned long long)seqp->ccid2s_seq); + hc->tx_pipe--; + } + if (seqp == hc->tx_seqt) { + done = 1; + break; + } + seqp = seqp->ccid2s_prev; + } + if (done) + break; + + ackno = SUB48(ackno_end_rl, 1); + } + if (done) + break; + } + + /* The state about what is acked should be correct now + * Check for NUMDUPACK + */ + seqp = hc->tx_seqt; + while (before48(seqp->ccid2s_seq, hc->tx_high_ack)) { + seqp = seqp->ccid2s_next; + if (seqp == hc->tx_seqh) { + seqp = hc->tx_seqh->ccid2s_prev; + break; + } + } + done = 0; + while (1) { + if (seqp->ccid2s_acked) { + done++; + if (done == NUMDUPACK) + break; + } + if (seqp == hc->tx_seqt) + break; + seqp = seqp->ccid2s_prev; + } + + /* If there are at least 3 acknowledgements, anything unacknowledged + * below the last sequence number is considered lost + */ + if (done == NUMDUPACK) { + struct ccid2_seq *last_acked = seqp; + + /* check for lost packets */ + while (1) { + if (!seqp->ccid2s_acked) { + ccid2_pr_debug("Packet lost: %llu\n", + (unsigned long long)seqp->ccid2s_seq); + /* XXX need to traverse from tail -> head in + * order to detect multiple congestion events in + * one ack vector. + */ + ccid2_congestion_event(sk, seqp); + hc->tx_pipe--; + } + if (seqp == hc->tx_seqt) + break; + seqp = seqp->ccid2s_prev; + } + + hc->tx_seqt = last_acked; + } + + /* trim acked packets in tail */ + while (hc->tx_seqt != hc->tx_seqh) { + if (!hc->tx_seqt->ccid2s_acked) + break; + + hc->tx_seqt = hc->tx_seqt->ccid2s_next; + } + + /* restart RTO timer if not all outstanding data has been acked */ + if (hc->tx_pipe == 0) + sk_stop_timer(sk, &hc->tx_rtotimer); + else + sk_reset_timer(sk, &hc->tx_rtotimer, jiffies + hc->tx_rto); +done: + /* check if incoming Acks allow pending packets to be sent */ + if (sender_was_blocked && !ccid2_cwnd_network_limited(hc)) + tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet); + dccp_ackvec_parsed_cleanup(&hc->tx_av_chunks); +} + +static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk) +{ + struct ccid2_hc_tx_sock *hc = ccid_priv(ccid); + struct dccp_sock *dp = dccp_sk(sk); + u32 max_ratio; + + /* RFC 4341, 5: initialise ssthresh to arbitrarily high (max) value */ + hc->tx_ssthresh = ~0U; + + /* Use larger initial windows (RFC 4341, section 5). */ + hc->tx_cwnd = rfc3390_bytes_to_packets(dp->dccps_mss_cache); + hc->tx_expected_wnd = hc->tx_cwnd; + + /* Make sure that Ack Ratio is enabled and within bounds. */ + max_ratio = DIV_ROUND_UP(hc->tx_cwnd, 2); + if (dp->dccps_l_ack_ratio == 0 || dp->dccps_l_ack_ratio > max_ratio) + dp->dccps_l_ack_ratio = max_ratio; + + /* XXX init ~ to window size... */ + if (ccid2_hc_tx_alloc_seq(hc)) + return -ENOMEM; + + hc->tx_rto = DCCP_TIMEOUT_INIT; + hc->tx_rpdupack = -1; + hc->tx_last_cong = hc->tx_lsndtime = hc->tx_cwnd_stamp = ccid2_time_stamp; + hc->tx_cwnd_used = 0; + setup_timer(&hc->tx_rtotimer, ccid2_hc_tx_rto_expire, + (unsigned long)sk); + INIT_LIST_HEAD(&hc->tx_av_chunks); + return 0; +} + +static void ccid2_hc_tx_exit(struct sock *sk) +{ + struct ccid2_hc_tx_sock *hc = ccid2_hc_tx_sk(sk); + int i; + + sk_stop_timer(sk, &hc->tx_rtotimer); + + for (i = 0; i < hc->tx_seqbufc; i++) + kfree(hc->tx_seqbuf[i]); + hc->tx_seqbufc = 0; +} + +static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) +{ + struct ccid2_hc_rx_sock *hc = ccid2_hc_rx_sk(sk); + + if (!dccp_data_packet(skb)) + return; + + if (++hc->rx_num_data_pkts >= dccp_sk(sk)->dccps_r_ack_ratio) { + dccp_send_ack(sk); + hc->rx_num_data_pkts = 0; + } +} + +struct ccid_operations ccid2_ops = { + .ccid_id = DCCPC_CCID2, + .ccid_name = "TCP-like", + .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock), + .ccid_hc_tx_init = ccid2_hc_tx_init, + .ccid_hc_tx_exit = ccid2_hc_tx_exit, + .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet, + .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent, + .ccid_hc_tx_parse_options = ccid2_hc_tx_parse_options, + .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv, + .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock), + .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv, +}; + +#ifdef CONFIG_IP_DCCP_CCID2_DEBUG +module_param(ccid2_debug, bool, 0644); +MODULE_PARM_DESC(ccid2_debug, "Enable CCID-2 debug messages"); +#endif diff --git a/net/dccp/ccids/ccid2.h b/net/dccp/ccids/ccid2.h new file mode 100644 index 00000000000..18c97543e52 --- /dev/null +++ b/net/dccp/ccids/ccid2.h @@ -0,0 +1,133 @@ +/* + * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#ifndef _DCCP_CCID2_H_ +#define _DCCP_CCID2_H_ + +#include <linux/timer.h> +#include <linux/types.h> +#include "../ccid.h" +#include "../dccp.h" + +/* + * CCID-2 timestamping faces the same issues as TCP timestamping. + * Hence we reuse/share as much of the code as possible. + */ +#define ccid2_time_stamp tcp_time_stamp + +/* NUMDUPACK parameter from RFC 4341, p. 6 */ +#define NUMDUPACK 3 + +struct ccid2_seq { + u64 ccid2s_seq; + u32 ccid2s_sent; + int ccid2s_acked; + struct ccid2_seq *ccid2s_prev; + struct ccid2_seq *ccid2s_next; +}; + +#define CCID2_SEQBUF_LEN 1024 +#define CCID2_SEQBUF_MAX 128 + +/* + * Multiple of congestion window to keep the sequence window at + * (RFC 4340 7.5.2) + */ +#define CCID2_WIN_CHANGE_FACTOR 5 + +/** + * struct ccid2_hc_tx_sock - CCID2 TX half connection + * @tx_{cwnd,ssthresh,pipe}: as per RFC 4341, section 5 + * @tx_packets_acked: Ack counter for deriving cwnd growth (RFC 3465) + * @tx_srtt: smoothed RTT estimate, scaled by 2^3 + * @tx_mdev: smoothed RTT variation, scaled by 2^2 + * @tx_mdev_max: maximum of @mdev during one flight + * @tx_rttvar: moving average/maximum of @mdev_max + * @tx_rto: RTO value deriving from SRTT and RTTVAR (RFC 2988) + * @tx_rtt_seq: to decay RTTVAR at most once per flight + * @tx_cwnd_used: actually used cwnd, W_used of RFC 2861 + * @tx_expected_wnd: moving average of @tx_cwnd_used + * @tx_cwnd_stamp: to track idle periods in CWV + * @tx_lsndtime: last time (in jiffies) a data packet was sent + * @tx_rpseq: last consecutive seqno + * @tx_rpdupack: dupacks since rpseq + * @tx_av_chunks: list of Ack Vectors received on current skb + */ +struct ccid2_hc_tx_sock { + u32 tx_cwnd; + u32 tx_ssthresh; + u32 tx_pipe; + u32 tx_packets_acked; + struct ccid2_seq *tx_seqbuf[CCID2_SEQBUF_MAX]; + int tx_seqbufc; + struct ccid2_seq *tx_seqh; + struct ccid2_seq *tx_seqt; + + /* RTT measurement: variables/principles are the same as in TCP */ + u32 tx_srtt, + tx_mdev, + tx_mdev_max, + tx_rttvar, + tx_rto; + u64 tx_rtt_seq:48; + struct timer_list tx_rtotimer; + + /* Congestion Window validation (optional, RFC 2861) */ + u32 tx_cwnd_used, + tx_expected_wnd, + tx_cwnd_stamp, + tx_lsndtime; + + u64 tx_rpseq; + int tx_rpdupack; + u32 tx_last_cong; + u64 tx_high_ack; + struct list_head tx_av_chunks; +}; + +static inline bool ccid2_cwnd_network_limited(struct ccid2_hc_tx_sock *hc) +{ + return hc->tx_pipe >= hc->tx_cwnd; +} + +/* + * Convert RFC 3390 larger initial window into an equivalent number of packets. + * This is based on the numbers specified in RFC 5681, 3.1. + */ +static inline u32 rfc3390_bytes_to_packets(const u32 smss) +{ + return smss <= 1095 ? 4 : (smss > 2190 ? 2 : 3); +} + +/** + * struct ccid2_hc_rx_sock - Receiving end of CCID-2 half-connection + * @rx_num_data_pkts: number of data packets received since last feedback + */ +struct ccid2_hc_rx_sock { + u32 rx_num_data_pkts; +}; + +static inline struct ccid2_hc_tx_sock *ccid2_hc_tx_sk(const struct sock *sk) +{ + return ccid_priv(dccp_sk(sk)->dccps_hc_tx_ccid); +} + +static inline struct ccid2_hc_rx_sock *ccid2_hc_rx_sk(const struct sock *sk) +{ + return ccid_priv(dccp_sk(sk)->dccps_hc_rx_ccid); +} +#endif /* _DCCP_CCID2_H_ */ diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index aa68e0ab274..119c04317d4 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -1,8 +1,7 @@ /* - * net/dccp/ccids/ccid3.c - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> * * An implementation of the DCCP protocol * @@ -33,1109 +32,806 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ - -#include <linux/config.h> -#include "../ccid.h" #include "../dccp.h" -#include "lib/packet_history.h" -#include "lib/loss_interval.h" -#include "lib/tfrc.h" #include "ccid3.h" -/* - * Reason for maths here is to avoid 32 bit overflow when a is big. - * With this we get close to the limit. - */ -static inline u32 usecs_div(const u32 a, const u32 b) -{ - const u32 div = a < (UINT_MAX / (USEC_PER_SEC / 10)) ? 10 : - a < (UINT_MAX / (USEC_PER_SEC / 50)) ? 50 : - a < (UINT_MAX / (USEC_PER_SEC / 100)) ? 100 : - a < (UINT_MAX / (USEC_PER_SEC / 500)) ? 500 : - a < (UINT_MAX / (USEC_PER_SEC / 1000)) ? 1000 : - a < (UINT_MAX / (USEC_PER_SEC / 5000)) ? 5000 : - a < (UINT_MAX / (USEC_PER_SEC / 10000)) ? 10000 : - a < (UINT_MAX / (USEC_PER_SEC / 50000)) ? 50000 : - 100000; - const u32 tmp = a * (USEC_PER_SEC / div); - return (b >= 2 * div) ? tmp / (b / div) : tmp; -} +#include <asm/unaligned.h> -static int ccid3_debug; - -#ifdef CCID3_DEBUG -#define ccid3_pr_debug(format, a...) \ - do { if (ccid3_debug) \ - printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \ - } while (0) +#ifdef CONFIG_IP_DCCP_CCID3_DEBUG +static bool ccid3_debug; +#define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a) #else #define ccid3_pr_debug(format, a...) #endif -static struct dccp_tx_hist *ccid3_tx_hist; -static struct dccp_rx_hist *ccid3_rx_hist; -static struct dccp_li_hist *ccid3_li_hist; - -static int ccid3_init(struct sock *sk) -{ - return 0; -} - -static void ccid3_exit(struct sock *sk) -{ -} - -/* TFRC sender states */ -enum ccid3_hc_tx_states { - TFRC_SSTATE_NO_SENT = 1, - TFRC_SSTATE_NO_FBACK, - TFRC_SSTATE_FBACK, - TFRC_SSTATE_TERM, -}; - -#ifdef CCID3_DEBUG +/* + * Transmitter Half-Connection Routines + */ +#ifdef CONFIG_IP_DCCP_CCID3_DEBUG static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state) { - static char *ccid3_state_names[] = { + static const char *const ccid3_state_names[] = { [TFRC_SSTATE_NO_SENT] = "NO_SENT", [TFRC_SSTATE_NO_FBACK] = "NO_FBACK", [TFRC_SSTATE_FBACK] = "FBACK", - [TFRC_SSTATE_TERM] = "TERM", }; return ccid3_state_names[state]; } #endif -static inline void ccid3_hc_tx_set_state(struct sock *sk, - enum ccid3_hc_tx_states state) +static void ccid3_hc_tx_set_state(struct sock *sk, + enum ccid3_hc_tx_states state) { - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state; + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + enum ccid3_hc_tx_states oldstate = hc->tx_state; ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", dccp_role(sk), sk, ccid3_tx_state_name(oldstate), ccid3_tx_state_name(state)); WARN_ON(state == oldstate); - hctx->ccid3hctx_state = state; + hc->tx_state = state; } -/* Calculate new t_ipi (inter packet interval) by t_ipi = s / X_inst */ -static inline void ccid3_calc_new_t_ipi(struct ccid3_hc_tx_sock *hctx) +/* + * Compute the initial sending rate X_init in the manner of RFC 3390: + * + * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT + * + * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis + * (rev-02) clarifies the use of RFC 3390 with regard to the above formula. + * For consistency with other parts of the code, X_init is scaled by 2^6. + */ +static inline u64 rfc3390_initial_rate(struct sock *sk) +{ + const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + const __u32 w_init = clamp_t(__u32, 4380U, 2 * hc->tx_s, 4 * hc->tx_s); + + return scaled_div(w_init << 6, hc->tx_rtt); +} + +/** + * ccid3_update_send_interval - Calculate new t_ipi = s / X_inst + * This respects the granularity of X_inst (64 * bytes/second). + */ +static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hc) +{ + hc->tx_t_ipi = scaled_div32(((u64)hc->tx_s) << 6, hc->tx_x); + + DCCP_BUG_ON(hc->tx_t_ipi == 0); + ccid3_pr_debug("t_ipi=%u, s=%u, X=%u\n", hc->tx_t_ipi, + hc->tx_s, (unsigned int)(hc->tx_x >> 6)); +} + +static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hc, ktime_t now) +{ + u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count); + + return delta / hc->tx_rtt; +} + +/** + * ccid3_hc_tx_update_x - Update allowed sending rate X + * @stamp: most recent time if available - can be left NULL. + * + * This function tracks draft rfc3448bis, check there for latest details. + * + * Note: X and X_recv are both stored in units of 64 * bytes/second, to support + * fine-grained resolution of sending rates. This requires scaling by 2^6 + * throughout the code. Only X_calc is unscaled (in bytes/second). + * + */ +static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) { + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + __u64 min_rate = 2 * hc->tx_x_recv; + const __u64 old_x = hc->tx_x; + ktime_t now = stamp ? *stamp : ktime_get_real(); + /* - * If no feedback spec says t_ipi is 1 second (set elsewhere and then - * doubles after every no feedback timer (separate function) + * Handle IDLE periods: do not reduce below RFC3390 initial sending rate + * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: + * a sender is idle if it has not sent anything over a 2-RTT-period. + * For consistency with X and X_recv, min_rate is also scaled by 2^6. */ - if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK) - hctx->ccid3hctx_t_ipi = usecs_div(hctx->ccid3hctx_s, - hctx->ccid3hctx_x); + if (ccid3_hc_tx_idle_rtt(hc, now) >= 2) { + min_rate = rfc3390_initial_rate(sk); + min_rate = max(min_rate, 2 * hc->tx_x_recv); + } + + if (hc->tx_p > 0) { + + hc->tx_x = min(((__u64)hc->tx_x_calc) << 6, min_rate); + hc->tx_x = max(hc->tx_x, (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); + + } else if (ktime_us_delta(now, hc->tx_t_ld) - (s64)hc->tx_rtt >= 0) { + + hc->tx_x = min(2 * hc->tx_x, min_rate); + hc->tx_x = max(hc->tx_x, + scaled_div(((__u64)hc->tx_s) << 6, hc->tx_rtt)); + hc->tx_t_ld = now; + } + + if (hc->tx_x != old_x) { + ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, " + "X_recv=%u\n", (unsigned int)(old_x >> 6), + (unsigned int)(hc->tx_x >> 6), hc->tx_x_calc, + (unsigned int)(hc->tx_x_recv >> 6)); + + ccid3_update_send_interval(hc); + } } -/* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */ -static inline void ccid3_calc_new_delta(struct ccid3_hc_tx_sock *hctx) +/** + * ccid3_hc_tx_update_s - Track the mean packet size `s' + * @len: DCCP packet payload size in bytes + * + * cf. RFC 4342, 5.3 and RFC 3448, 4.1 + */ +static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hc, int len) { - hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2, - TFRC_OPSYS_HALF_TIME_GRAN); + const u16 old_s = hc->tx_s; + + hc->tx_s = tfrc_ewma(hc->tx_s, len, 9); + + if (hc->tx_s != old_s) + ccid3_update_send_interval(hc); } /* - * Update X by - * If (p > 0) - * x_calc = calcX(s, R, p); - * X = max(min(X_calc, 2 * X_recv), s / t_mbi); - * Else - * If (now - tld >= R) - * X = max(min(2 * X, 2 * X_recv), s / R); - * tld = now; - */ -static void ccid3_hc_tx_update_x(struct sock *sk) + * Update Window Counter using the algorithm from [RFC 4342, 8.1]. + * As elsewhere, RTT > 0 is assumed by using dccp_sample_rtt(). + */ +static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hc, + ktime_t now) { - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - - /* To avoid large error in calcX */ - if (hctx->ccid3hctx_p >= TFRC_SMALLEST_P) { - hctx->ccid3hctx_x_calc = tfrc_calc_x(hctx->ccid3hctx_s, - hctx->ccid3hctx_rtt, - hctx->ccid3hctx_p); - hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_calc, - 2 * hctx->ccid3hctx_x_recv), - (hctx->ccid3hctx_s / - TFRC_MAX_BACK_OFF_TIME)); - } else { - struct timeval now; - - dccp_timestamp(sk, &now); - if (timeval_delta(&now, &hctx->ccid3hctx_t_ld) >= - hctx->ccid3hctx_rtt) { - hctx->ccid3hctx_x = max_t(u32, min_t(u32, hctx->ccid3hctx_x_recv, - hctx->ccid3hctx_x) * 2, - usecs_div(hctx->ccid3hctx_s, - hctx->ccid3hctx_rtt)); - hctx->ccid3hctx_t_ld = now; - } + u32 delta = ktime_us_delta(now, hc->tx_t_last_win_count), + quarter_rtts = (4 * delta) / hc->tx_rtt; + + if (quarter_rtts > 0) { + hc->tx_t_last_win_count = now; + hc->tx_last_win_count += min(quarter_rtts, 5U); + hc->tx_last_win_count &= 0xF; /* mod 16 */ } } static void ccid3_hc_tx_no_feedback_timer(unsigned long data) { struct sock *sk = (struct sock *)data; - unsigned long next_tmout = 0; - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + unsigned long t_nfb = USEC_PER_SEC / 5; bh_lock_sock(sk); if (sock_owned_by_user(sk)) { /* Try again later. */ /* XXX: set some sensible MIB */ - sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, - jiffies + HZ / 5); - goto out; + goto restart_timer; } - ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk, - ccid3_tx_state_name(hctx->ccid3hctx_state)); - - switch (hctx->ccid3hctx_state) { - case TFRC_SSTATE_TERM: + ccid3_pr_debug("%s(%p, state=%s) - entry\n", dccp_role(sk), sk, + ccid3_tx_state_name(hc->tx_state)); + + /* Ignore and do not restart after leaving the established state */ + if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) goto out; - case TFRC_SSTATE_NO_FBACK: - /* Halve send rate */ - hctx->ccid3hctx_x /= 2; - if (hctx->ccid3hctx_x < (hctx->ccid3hctx_s / - TFRC_MAX_BACK_OFF_TIME)) - hctx->ccid3hctx_x = (hctx->ccid3hctx_s / - TFRC_MAX_BACK_OFF_TIME); - - ccid3_pr_debug("%s, sk=%p, state=%s, updated tx rate to %d " - "bytes/s\n", - dccp_role(sk), sk, - ccid3_tx_state_name(hctx->ccid3hctx_state), - hctx->ccid3hctx_x); - next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s, - hctx->ccid3hctx_x), - TFRC_INITIAL_TIMEOUT); - /* - * FIXME - not sure above calculation is correct. See section - * 5 of CCID3 11 should adjust tx_t_ipi and double that to - * achieve it really - */ - break; - case TFRC_SSTATE_FBACK: + + /* Reset feedback state to "no feedback received" */ + if (hc->tx_state == TFRC_SSTATE_FBACK) + ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); + + /* + * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4 + * RTO is 0 if and only if no feedback has been received yet. + */ + if (hc->tx_t_rto == 0 || hc->tx_p == 0) { + + /* halve send rate directly */ + hc->tx_x = max(hc->tx_x / 2, + (((__u64)hc->tx_s) << 6) / TFRC_T_MBI); + ccid3_update_send_interval(hc); + } else { /* - * Check if IDLE since last timeout and recv rate is less than - * 4 packets per RTT + * Modify the cached value of X_recv + * + * If (X_calc > 2 * X_recv) + * X_recv = max(X_recv / 2, s / (2 * t_mbi)); + * Else + * X_recv = X_calc / 4; + * + * Note that X_recv is scaled by 2^6 while X_calc is not */ - if (!hctx->ccid3hctx_idle || - (hctx->ccid3hctx_x_recv >= - 4 * usecs_div(hctx->ccid3hctx_s, hctx->ccid3hctx_rtt))) { - ccid3_pr_debug("%s, sk=%p, state=%s, not idle\n", - dccp_role(sk), sk, - ccid3_tx_state_name(hctx->ccid3hctx_state)); - /* Halve sending rate */ - - /* If (X_calc > 2 * X_recv) - * X_recv = max(X_recv / 2, s / (2 * t_mbi)); - * Else - * X_recv = X_calc / 4; - */ - BUG_ON(hctx->ccid3hctx_p >= TFRC_SMALLEST_P && - hctx->ccid3hctx_x_calc == 0); - - /* check also if p is zero -> x_calc is infinity? */ - if (hctx->ccid3hctx_p < TFRC_SMALLEST_P || - hctx->ccid3hctx_x_calc > 2 * hctx->ccid3hctx_x_recv) - hctx->ccid3hctx_x_recv = max_t(u32, hctx->ccid3hctx_x_recv / 2, - hctx->ccid3hctx_s / (2 * TFRC_MAX_BACK_OFF_TIME)); - else - hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc / 4; - - /* Update sending rate */ - ccid3_hc_tx_update_x(sk); + if (hc->tx_x_calc > (hc->tx_x_recv >> 5)) + hc->tx_x_recv = + max(hc->tx_x_recv / 2, + (((__u64)hc->tx_s) << 6) / (2*TFRC_T_MBI)); + else { + hc->tx_x_recv = hc->tx_x_calc; + hc->tx_x_recv <<= 4; } - /* - * Schedule no feedback timer to expire in - * max(4 * R, 2 * s / X) - */ - next_tmout = max_t(u32, hctx->ccid3hctx_t_rto, - 2 * usecs_div(hctx->ccid3hctx_s, - hctx->ccid3hctx_x)); - break; - default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); - dump_stack(); - goto out; + ccid3_hc_tx_update_x(sk, NULL); } + ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n", + (unsigned long long)hc->tx_x); + + /* + * Set new timeout for the nofeedback timer. + * See comments in packet_recv() regarding the value of t_RTO. + */ + if (unlikely(hc->tx_t_rto == 0)) /* no feedback received yet */ + t_nfb = TFRC_INITIAL_TIMEOUT; + else + t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); - sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, - jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); - hctx->ccid3hctx_idle = 1; +restart_timer: + sk_reset_timer(sk, &hc->tx_no_feedback_timer, + jiffies + usecs_to_jiffies(t_nfb)); out: bh_unlock_sock(sk); sock_put(sk); } -static int ccid3_hc_tx_send_packet(struct sock *sk, - struct sk_buff *skb, int len) +/** + * ccid3_hc_tx_send_packet - Delay-based dequeueing of TX packets + * @skb: next packet candidate to send on @sk + * + * This function uses the convention of ccid_packet_dequeue_eval() and + * returns a millisecond-delay value between 0 and t_mbi = 64000 msec. + */ +static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - struct dccp_tx_hist_entry *new_packet; - struct timeval now; - long delay; - int rc = -ENOTCONN; + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + ktime_t now = ktime_get_real(); + s64 delay; - BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); - - /* Check if pure ACK or Terminating*/ /* - * XXX: We only call this function for DATA and DATAACK, on, these - * packets can have zero length, but why the comment about "pure ACK"? + * This function is called only for Data and DataAck packets. Sending + * zero-sized Data(Ack)s is theoretically possible, but for congestion + * control this case is pathological - ignore it. */ - if (unlikely(len == 0)) - goto out; + if (unlikely(skb->len == 0)) + return -EBADMSG; - /* See if last packet allocated was not sent */ - new_packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); - if (new_packet == NULL || new_packet->dccphtx_sent) { - new_packet = dccp_tx_hist_entry_new(ccid3_tx_hist, - SLAB_ATOMIC); - - rc = -ENOBUFS; - if (unlikely(new_packet == NULL)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, not enough " - "mem to add to history, send refused\n", - __FUNCTION__, dccp_role(sk), sk); - goto out; - } + if (hc->tx_state == TFRC_SSTATE_NO_SENT) { + sk_reset_timer(sk, &hc->tx_no_feedback_timer, (jiffies + + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT))); + hc->tx_last_win_count = 0; + hc->tx_t_last_win_count = now; - dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, new_packet); - } + /* Set t_0 for initial packet */ + hc->tx_t_nom = now; - dccp_timestamp(sk, &now); + hc->tx_s = skb->len; + + /* + * Use initial RTT sample when available: recommended by erratum + * to RFC 4342. This implements the initialisation procedure of + * draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6. + */ + if (dp->dccps_syn_rtt) { + ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt); + hc->tx_rtt = dp->dccps_syn_rtt; + hc->tx_x = rfc3390_initial_rate(sk); + hc->tx_t_ld = now; + } else { + /* + * Sender does not have RTT sample: + * - set fallback RTT (RFC 4340, 3.4) since a RTT value + * is needed in several parts (e.g. window counter); + * - set sending rate X_pps = 1pps as per RFC 3448, 4.2. + */ + hc->tx_rtt = DCCP_FALLBACK_RTT; + hc->tx_x = hc->tx_s; + hc->tx_x <<= 6; + } + ccid3_update_send_interval(hc); - switch (hctx->ccid3hctx_state) { - case TFRC_SSTATE_NO_SENT: - hctx->ccid3hctx_no_feedback_timer.function = ccid3_hc_tx_no_feedback_timer; - hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk; - sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, - jiffies + usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)); - hctx->ccid3hctx_last_win_count = 0; - hctx->ccid3hctx_t_last_win_count = now; ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK); - hctx->ccid3hctx_t_ipi = TFRC_INITIAL_IPI; - - /* Set nominal send time for initial packet */ - hctx->ccid3hctx_t_nom = now; - timeval_add_usecs(&hctx->ccid3hctx_t_nom, - hctx->ccid3hctx_t_ipi); - ccid3_calc_new_delta(hctx); - rc = 0; - break; - case TFRC_SSTATE_NO_FBACK: - case TFRC_SSTATE_FBACK: - delay = (timeval_delta(&now, &hctx->ccid3hctx_t_nom) - - hctx->ccid3hctx_delta); - delay /= -1000; - /* divide by -1000 is to convert to ms and get sign right */ - rc = delay > 0 ? delay : 0; - break; - default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); - dump_stack(); - rc = -EINVAL; - break; - } - /* Can we send? if so add options and add to packet history */ - if (rc == 0) { - dp->dccps_hc_tx_insert_options = 1; - new_packet->dccphtx_ccval = - DCCP_SKB_CB(skb)->dccpd_ccval = - hctx->ccid3hctx_last_win_count; - } -out: - return rc; -} + } else { + delay = ktime_us_delta(hc->tx_t_nom, now); + ccid3_pr_debug("delay=%ld\n", (long)delay); + /* + * Scheduling of packet transmissions (RFC 5348, 8.3) + * + * if (t_now > t_nom - delta) + * // send the packet now + * else + * // send the packet in (t_nom - t_now) milliseconds. + */ + if (delay >= TFRC_T_DELTA) + return (u32)delay / USEC_PER_MSEC; -static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, int len) -{ - const struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - struct timeval now; + ccid3_hc_tx_update_win_count(hc, now); + } - BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); + /* prepare to send now (add options etc.) */ + dp->dccps_hc_tx_insert_options = 1; + DCCP_SKB_CB(skb)->dccpd_ccval = hc->tx_last_win_count; - dccp_timestamp(sk, &now); + /* set the nominal send time for the next following packet */ + hc->tx_t_nom = ktime_add_us(hc->tx_t_nom, hc->tx_t_ipi); + return CCID_PACKET_SEND_AT_ONCE; +} - /* check if we have sent a data packet */ - if (len > 0) { - unsigned long quarter_rtt; - struct dccp_tx_hist_entry *packet; +static void ccid3_hc_tx_packet_sent(struct sock *sk, unsigned int len) +{ + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); - packet = dccp_tx_hist_head(&hctx->ccid3hctx_hist); - if (unlikely(packet == NULL)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: packet doesn't " - "exists in history!\n", __FUNCTION__); - return; - } - if (unlikely(packet->dccphtx_sent)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: no unsent packet in " - "history!\n", __FUNCTION__); - return; - } - packet->dccphtx_tstamp = now; - packet->dccphtx_seqno = dp->dccps_gss; - /* - * Check if win_count have changed - * Algorithm in "8.1. Window Counter Valuer" in - * draft-ietf-dccp-ccid3-11.txt - */ - quarter_rtt = timeval_delta(&now, &hctx->ccid3hctx_t_last_win_count); - if (likely(hctx->ccid3hctx_rtt > 8)) - quarter_rtt /= hctx->ccid3hctx_rtt / 4; - - if (quarter_rtt > 0) { - hctx->ccid3hctx_t_last_win_count = now; - hctx->ccid3hctx_last_win_count = (hctx->ccid3hctx_last_win_count + - min_t(unsigned long, quarter_rtt, 5)) % 16; - ccid3_pr_debug("%s, sk=%p, window changed from " - "%u to %u!\n", - dccp_role(sk), sk, - packet->dccphtx_ccval, - hctx->ccid3hctx_last_win_count); - } + ccid3_hc_tx_update_s(hc, len); - hctx->ccid3hctx_idle = 0; - packet->dccphtx_rtt = hctx->ccid3hctx_rtt; - packet->dccphtx_sent = 1; - } else - ccid3_pr_debug("%s, sk=%p, seqno=%llu NOT inserted!\n", - dccp_role(sk), sk, dp->dccps_gss); - - switch (hctx->ccid3hctx_state) { - case TFRC_SSTATE_NO_SENT: - /* if first wasn't pure ack */ - if (len != 0) - printk(KERN_CRIT "%s: %s, First packet sent is noted " - "as a data packet\n", - __FUNCTION__, dccp_role(sk)); - return; - case TFRC_SSTATE_NO_FBACK: - case TFRC_SSTATE_FBACK: - if (len > 0) { - hctx->ccid3hctx_t_nom = now; - ccid3_calc_new_t_ipi(hctx); - ccid3_calc_new_delta(hctx); - timeval_add_usecs(&hctx->ccid3hctx_t_nom, - hctx->ccid3hctx_t_ipi); - } - break; - default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); - dump_stack(); - break; - } + if (tfrc_tx_hist_add(&hc->tx_hist, dccp_sk(sk)->dccps_gss)) + DCCP_CRIT("packet history - out of memory!"); } static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) { - const struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - struct ccid3_options_received *opt_recv; - struct dccp_tx_hist_entry *packet; - struct timeval now; - unsigned long next_tmout; - u32 t_elapsed; - u32 pinv; - u32 x_recv; + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + struct tfrc_tx_hist_entry *acked; + ktime_t now; + unsigned long t_nfb; u32 r_sample; - BUG_ON(hctx == NULL || hctx->ccid3hctx_state == TFRC_SSTATE_TERM); - /* we are only interested in ACKs */ if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK || DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK)) return; + /* + * Locate the acknowledged packet in the TX history. + * + * Returning "entry not found" here can for instance happen when + * - the host has not sent out anything (e.g. a passive server), + * - the Ack is outdated (packet with higher Ack number was received), + * - it is a bogus Ack (for a packet not sent on this connection). + */ + acked = tfrc_tx_hist_find_entry(hc->tx_hist, dccp_hdr_ack_seq(skb)); + if (acked == NULL) + return; + /* For the sake of RTT sampling, ignore/remove all older entries */ + tfrc_tx_hist_purge(&acked->next); - opt_recv = &hctx->ccid3hctx_options_received; + /* Update the moving average for the RTT estimate (RFC 3448, 4.3) */ + now = ktime_get_real(); + r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, acked->stamp)); + hc->tx_rtt = tfrc_ewma(hc->tx_rtt, r_sample, 9); - t_elapsed = dp->dccps_options_received.dccpor_elapsed_time * 10; - x_recv = opt_recv->ccid3or_receive_rate; - pinv = opt_recv->ccid3or_loss_event_rate; + /* + * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3 + */ + if (hc->tx_state == TFRC_SSTATE_NO_FBACK) { + ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); - switch (hctx->ccid3hctx_state) { - case TFRC_SSTATE_NO_SENT: - /* FIXME: what to do here? */ - return; - case TFRC_SSTATE_NO_FBACK: - case TFRC_SSTATE_FBACK: - /* Calculate new round trip sample by - * R_sample = (now - t_recvdata) - t_delay */ - /* get t_recvdata from history */ - packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist, - DCCP_SKB_CB(skb)->dccpd_ack_seq); - if (unlikely(packet == NULL)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, seqno " - "%llu(%s) does't exist in history!\n", - __FUNCTION__, dccp_role(sk), sk, - (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, - dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type)); - return; - } + if (hc->tx_t_rto == 0) { + /* + * Initial feedback packet: Larger Initial Windows (4.2) + */ + hc->tx_x = rfc3390_initial_rate(sk); + hc->tx_t_ld = now; - /* Update RTT */ - dccp_timestamp(sk, &now); - r_sample = timeval_delta(&now, &packet->dccphtx_tstamp); - if (unlikely(r_sample <= t_elapsed)) - LIMIT_NETDEBUG(KERN_WARNING "%s: r_sample=%uus, " - "t_elapsed=%uus\n", - __FUNCTION__, r_sample, t_elapsed); - else - r_sample -= t_elapsed; + ccid3_update_send_interval(hc); - /* Update RTT estimate by - * If (No feedback recv) - * R = R_sample; - * Else - * R = q * R + (1 - q) * R_sample; - * - * q is a constant, RFC 3448 recomments 0.9 - */ - if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) { - ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK); - hctx->ccid3hctx_rtt = r_sample; - } else - hctx->ccid3hctx_rtt = (hctx->ccid3hctx_rtt * 9) / 10 + - r_sample / 10; - - ccid3_pr_debug("%s, sk=%p, New RTT estimate=%uus, " - "r_sample=%us\n", dccp_role(sk), sk, - hctx->ccid3hctx_rtt, r_sample); - - /* Update timeout interval */ - hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt, - USEC_PER_SEC); - - /* Update receive rate */ - hctx->ccid3hctx_x_recv = x_recv;/* X_recv in bytes per sec */ - - /* Update loss event rate */ - if (pinv == ~0 || pinv == 0) - hctx->ccid3hctx_p = 0; - else { - hctx->ccid3hctx_p = 1000000 / pinv; - - if (hctx->ccid3hctx_p < TFRC_SMALLEST_P) { - hctx->ccid3hctx_p = TFRC_SMALLEST_P; - ccid3_pr_debug("%s, sk=%p, Smallest p used!\n", - dccp_role(sk), sk); - } + goto done_computing_x; + } else if (hc->tx_p == 0) { + /* + * First feedback after nofeedback timer expiry (4.3) + */ + goto done_computing_x; } + } - /* unschedule no feedback timer */ - sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); - - /* Update sending rate */ - ccid3_hc_tx_update_x(sk); + /* Update sending rate (step 4 of [RFC 3448, 4.3]) */ + if (hc->tx_p > 0) + hc->tx_x_calc = tfrc_calc_x(hc->tx_s, hc->tx_rtt, hc->tx_p); + ccid3_hc_tx_update_x(sk, &now); - /* Update next send time */ - timeval_sub_usecs(&hctx->ccid3hctx_t_nom, - hctx->ccid3hctx_t_ipi); - ccid3_calc_new_t_ipi(hctx); - timeval_add_usecs(&hctx->ccid3hctx_t_nom, - hctx->ccid3hctx_t_ipi); - ccid3_calc_new_delta(hctx); +done_computing_x: + ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, " + "p=%u, X_calc=%u, X_recv=%u, X=%u\n", + dccp_role(sk), sk, hc->tx_rtt, r_sample, + hc->tx_s, hc->tx_p, hc->tx_x_calc, + (unsigned int)(hc->tx_x_recv >> 6), + (unsigned int)(hc->tx_x >> 6)); - /* remove all packets older than the one acked from history */ - dccp_tx_hist_purge_older(ccid3_tx_hist, - &hctx->ccid3hctx_hist, packet); - /* - * As we have calculated new ipi, delta, t_nom it is possible that - * we now can send a packet, so wake up dccp_wait_for_ccids. - */ - sk->sk_write_space(sk); + /* unschedule no feedback timer */ + sk_stop_timer(sk, &hc->tx_no_feedback_timer); - /* - * Schedule no feedback timer to expire in - * max(4 * R, 2 * s / X) - */ - next_tmout = max(hctx->ccid3hctx_t_rto, - 2 * usecs_div(hctx->ccid3hctx_s, - hctx->ccid3hctx_x)); - - ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to " - "expire in %lu jiffies (%luus)\n", - dccp_role(sk), sk, - usecs_to_jiffies(next_tmout), next_tmout); - - sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, - jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout))); - - /* set idle flag */ - hctx->ccid3hctx_idle = 1; - break; - default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hctx->ccid3hctx_state); - dump_stack(); - break; - } -} - -static void ccid3_hc_tx_insert_options(struct sock *sk, struct sk_buff *skb) -{ - const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); + /* + * As we have calculated new ipi, delta, t_nom it is possible + * that we now can send a packet, so wake up dccp_wait_for_ccid + */ + sk->sk_write_space(sk); - BUG_ON(hctx == NULL); + /* + * Update timeout interval for the nofeedback timer. In order to control + * rate halving on networks with very low RTTs (<= 1 ms), use per-route + * tunable RTAX_RTO_MIN value as the lower bound. + */ + hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt, + USEC_PER_SEC/HZ * tcp_rto_min(sk)); + /* + * Schedule no feedback timer to expire in + * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) + */ + t_nfb = max(hc->tx_t_rto, 2 * hc->tx_t_ipi); - if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) - return; + ccid3_pr_debug("%s(%p), Scheduled no feedback timer to " + "expire in %lu jiffies (%luus)\n", + dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb); - DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; + sk_reset_timer(sk, &hc->tx_no_feedback_timer, + jiffies + usecs_to_jiffies(t_nfb)); } -static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option, - unsigned char len, u16 idx, - unsigned char *value) +static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type, + u8 option, u8 *optval, u8 optlen) { - int rc = 0; - const struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - struct ccid3_options_received *opt_recv; - - BUG_ON(hctx == NULL); - - opt_recv = &hctx->ccid3hctx_options_received; - - if (opt_recv->ccid3or_seqno != dp->dccps_gsr) { - opt_recv->ccid3or_seqno = dp->dccps_gsr; - opt_recv->ccid3or_loss_event_rate = ~0; - opt_recv->ccid3or_loss_intervals_idx = 0; - opt_recv->ccid3or_loss_intervals_len = 0; - opt_recv->ccid3or_receive_rate = 0; - } + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + __be32 opt_val; switch (option) { + case TFRC_OPT_RECEIVE_RATE: case TFRC_OPT_LOSS_EVENT_RATE: - if (unlikely(len != 4)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, invalid " - "len for TFRC_OPT_LOSS_EVENT_RATE\n", - __FUNCTION__, dccp_role(sk), sk); - rc = -EINVAL; - } else { - opt_recv->ccid3or_loss_event_rate = ntohl(*(u32 *)value); - ccid3_pr_debug("%s, sk=%p, LOSS_EVENT_RATE=%u\n", - dccp_role(sk), sk, - opt_recv->ccid3or_loss_event_rate); + /* Must be ignored on Data packets, cf. RFC 4342 8.3 and 8.5 */ + if (packet_type == DCCP_PKT_DATA) + break; + if (unlikely(optlen != 4)) { + DCCP_WARN("%s(%p), invalid len %d for %u\n", + dccp_role(sk), sk, optlen, option); + return -EINVAL; } - break; - case TFRC_OPT_LOSS_INTERVALS: - opt_recv->ccid3or_loss_intervals_idx = idx; - opt_recv->ccid3or_loss_intervals_len = len; - ccid3_pr_debug("%s, sk=%p, LOSS_INTERVALS=(%u, %u)\n", - dccp_role(sk), sk, - opt_recv->ccid3or_loss_intervals_idx, - opt_recv->ccid3or_loss_intervals_len); - break; - case TFRC_OPT_RECEIVE_RATE: - if (unlikely(len != 4)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, invalid " - "len for TFRC_OPT_RECEIVE_RATE\n", - __FUNCTION__, dccp_role(sk), sk); - rc = -EINVAL; + opt_val = ntohl(get_unaligned((__be32 *)optval)); + + if (option == TFRC_OPT_RECEIVE_RATE) { + /* Receive Rate is kept in units of 64 bytes/second */ + hc->tx_x_recv = opt_val; + hc->tx_x_recv <<= 6; + + ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n", + dccp_role(sk), sk, opt_val); } else { - opt_recv->ccid3or_receive_rate = ntohl(*(u32 *)value); - ccid3_pr_debug("%s, sk=%p, RECEIVE_RATE=%u\n", - dccp_role(sk), sk, - opt_recv->ccid3or_receive_rate); + /* Update the fixpoint Loss Event Rate fraction */ + hc->tx_p = tfrc_invert_loss_event_rate(opt_val); + + ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n", + dccp_role(sk), sk, opt_val); } - break; } - - return rc; + return 0; } -static int ccid3_hc_tx_init(struct sock *sk) +static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx; - - dp->dccps_hc_tx_ccid_private = kmalloc(sizeof(*hctx), gfp_any()); - if (dp->dccps_hc_tx_ccid_private == NULL) - return -ENOMEM; - - hctx = ccid3_hc_tx_sk(sk); - memset(hctx, 0, sizeof(*hctx)); - - if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && - dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) - hctx->ccid3hctx_s = dp->dccps_packet_size; - else - hctx->ccid3hctx_s = TFRC_STD_PACKET_SIZE; - - /* Set transmission rate to 1 packet per second */ - hctx->ccid3hctx_x = hctx->ccid3hctx_s; - hctx->ccid3hctx_t_rto = USEC_PER_SEC; - hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT; - INIT_LIST_HEAD(&hctx->ccid3hctx_hist); - init_timer(&hctx->ccid3hctx_no_feedback_timer); + struct ccid3_hc_tx_sock *hc = ccid_priv(ccid); + hc->tx_state = TFRC_SSTATE_NO_SENT; + hc->tx_hist = NULL; + setup_timer(&hc->tx_no_feedback_timer, + ccid3_hc_tx_no_feedback_timer, (unsigned long)sk); return 0; } static void ccid3_hc_tx_exit(struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); + struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); - BUG_ON(hctx == NULL); + sk_stop_timer(sk, &hc->tx_no_feedback_timer); + tfrc_tx_hist_purge(&hc->tx_hist); +} - ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM); - sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer); +static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) +{ + info->tcpi_rto = ccid3_hc_tx_sk(sk)->tx_t_rto; + info->tcpi_rtt = ccid3_hc_tx_sk(sk)->tx_rtt; +} + +static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, + u32 __user *optval, int __user *optlen) +{ + const struct ccid3_hc_tx_sock *hc = ccid3_hc_tx_sk(sk); + struct tfrc_tx_info tfrc; + const void *val; + + switch (optname) { + case DCCP_SOCKOPT_CCID_TX_INFO: + if (len < sizeof(tfrc)) + return -EINVAL; + memset(&tfrc, 0, sizeof(tfrc)); + tfrc.tfrctx_x = hc->tx_x; + tfrc.tfrctx_x_recv = hc->tx_x_recv; + tfrc.tfrctx_x_calc = hc->tx_x_calc; + tfrc.tfrctx_rtt = hc->tx_rtt; + tfrc.tfrctx_p = hc->tx_p; + tfrc.tfrctx_rto = hc->tx_t_rto; + tfrc.tfrctx_ipi = hc->tx_t_ipi; + len = sizeof(tfrc); + val = &tfrc; + break; + default: + return -ENOPROTOOPT; + } - /* Empty packet history */ - dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist); + if (put_user(len, optlen) || copy_to_user(optval, val, len)) + return -EFAULT; - kfree(dp->dccps_hc_tx_ccid_private); - dp->dccps_hc_tx_ccid_private = NULL; + return 0; } /* - * RX Half Connection methods + * Receiver Half-Connection Routines */ -/* TFRC receiver states */ -enum ccid3_hc_rx_states { - TFRC_RSTATE_NO_DATA = 1, - TFRC_RSTATE_DATA, - TFRC_RSTATE_TERM = 127, +/* CCID3 feedback types */ +enum ccid3_fback_type { + CCID3_FBACK_NONE = 0, + CCID3_FBACK_INITIAL, + CCID3_FBACK_PERIODIC, + CCID3_FBACK_PARAM_CHANGE }; -#ifdef CCID3_DEBUG +#ifdef CONFIG_IP_DCCP_CCID3_DEBUG static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state) { - static char *ccid3_rx_state_names[] = { + static const char *const ccid3_rx_state_names[] = { [TFRC_RSTATE_NO_DATA] = "NO_DATA", [TFRC_RSTATE_DATA] = "DATA", - [TFRC_RSTATE_TERM] = "TERM", }; return ccid3_rx_state_names[state]; } #endif -static inline void ccid3_hc_rx_set_state(struct sock *sk, - enum ccid3_hc_rx_states state) +static void ccid3_hc_rx_set_state(struct sock *sk, + enum ccid3_hc_rx_states state) { - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state; + struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); + enum ccid3_hc_rx_states oldstate = hc->rx_state; ccid3_pr_debug("%s(%p) %-8.8s -> %s\n", dccp_role(sk), sk, ccid3_rx_state_name(oldstate), ccid3_rx_state_name(state)); WARN_ON(state == oldstate); - hcrx->ccid3hcrx_state = state; + hc->rx_state = state; } -static void ccid3_hc_rx_send_feedback(struct sock *sk) +static void ccid3_hc_rx_send_feedback(struct sock *sk, + const struct sk_buff *skb, + enum ccid3_fback_type fbtype) { - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); + struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); struct dccp_sock *dp = dccp_sk(sk); - struct dccp_rx_hist_entry *packet; - struct timeval now; - - ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); + ktime_t now = ktime_get_real(); + s64 delta = 0; - dccp_timestamp(sk, &now); - - switch (hcrx->ccid3hcrx_state) { - case TFRC_RSTATE_NO_DATA: - hcrx->ccid3hcrx_x_recv = 0; + switch (fbtype) { + case CCID3_FBACK_INITIAL: + hc->rx_x_recv = 0; + hc->rx_pinv = ~0U; /* see RFC 4342, 8.5 */ break; - case TFRC_RSTATE_DATA: { - const u32 delta = timeval_delta(&now, - &hcrx->ccid3hcrx_tstamp_last_feedback); - hcrx->ccid3hcrx_x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, - delta); - } + case CCID3_FBACK_PARAM_CHANGE: + /* + * When parameters change (new loss or p > p_prev), we do not + * have a reliable estimate for R_m of [RFC 3448, 6.2] and so + * need to reuse the previous value of X_recv. However, when + * X_recv was 0 (due to early loss), this would kill X down to + * s/t_mbi (i.e. one packet in 64 seconds). + * To avoid such drastic reduction, we approximate X_recv as + * the number of bytes since last feedback. + * This is a safe fallback, since X is bounded above by X_calc. + */ + if (hc->rx_x_recv > 0) + break; + /* fall through */ + case CCID3_FBACK_PERIODIC: + delta = ktime_us_delta(now, hc->rx_tstamp_last_feedback); + if (delta <= 0) + DCCP_BUG("delta (%ld) <= 0", (long)delta); + else + hc->rx_x_recv = scaled_div32(hc->rx_bytes_recv, delta); break; default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); - dump_stack(); return; } - packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist); - if (unlikely(packet == NULL)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, no data packet " - "in history!\n", - __FUNCTION__, dccp_role(sk), sk); - return; - } + ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta, + hc->rx_x_recv, hc->rx_pinv); - hcrx->ccid3hcrx_tstamp_last_feedback = now; - hcrx->ccid3hcrx_last_counter = packet->dccphrx_ccval; - hcrx->ccid3hcrx_seqno_last_counter = packet->dccphrx_seqno; - hcrx->ccid3hcrx_bytes_recv = 0; + hc->rx_tstamp_last_feedback = now; + hc->rx_last_counter = dccp_hdr(skb)->dccph_ccval; + hc->rx_bytes_recv = 0; - /* Convert to multiples of 10us */ - hcrx->ccid3hcrx_elapsed_time = - timeval_delta(&now, &packet->dccphrx_tstamp) / 10; - if (hcrx->ccid3hcrx_p == 0) - hcrx->ccid3hcrx_pinv = ~0; - else - hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p; dp->dccps_hc_rx_insert_options = 1; dccp_send_ack(sk); } -static void ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) +static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb) { - const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - u32 x_recv, pinv; - - BUG_ON(hcrx == NULL); + const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); + __be32 x_recv, pinv; if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN)) - return; - - DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_last_counter; + return 0; if (dccp_packet_without_ack(skb)) - return; - - if (hcrx->ccid3hcrx_elapsed_time != 0) - dccp_insert_option_elapsed_time(sk, skb, - hcrx->ccid3hcrx_elapsed_time); - dccp_insert_option_timestamp(sk, skb); - x_recv = htonl(hcrx->ccid3hcrx_x_recv); - pinv = htonl(hcrx->ccid3hcrx_pinv); - dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE, - &pinv, sizeof(pinv)); - dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE, - &x_recv, sizeof(x_recv)); + return 0; + + x_recv = htonl(hc->rx_x_recv); + pinv = htonl(hc->rx_pinv); + + if (dccp_insert_option(skb, TFRC_OPT_LOSS_EVENT_RATE, + &pinv, sizeof(pinv)) || + dccp_insert_option(skb, TFRC_OPT_RECEIVE_RATE, + &x_recv, sizeof(x_recv))) + return -1; + + return 0; } -/* calculate first loss interval +/** + * ccid3_first_li - Implements [RFC 5348, 6.3.1] * - * returns estimated loss interval in usecs */ - -static u32 ccid3_hc_rx_calc_first_li(struct sock *sk) + * Determine the length of the first loss interval via inverse lookup. + * Assume that X_recv can be computed by the throughput equation + * s + * X_recv = -------- + * R * fval + * Find some p such that f(p) = fval; return 1/p (scaled). + */ +static u32 ccid3_first_li(struct sock *sk) { - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - struct dccp_rx_hist_entry *entry, *next, *tail = NULL; - u32 rtt, delta, x_recv, fval, p, tmp2; - struct timeval tstamp = { 0, }; - int interval = 0; - int win_count = 0; - int step = 0; - u64 tmp1; - - list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist, - dccphrx_node) { - if (dccp_rx_hist_entry_data_packet(entry)) { - tail = entry; - - switch (step) { - case 0: - tstamp = entry->dccphrx_tstamp; - win_count = entry->dccphrx_ccval; - step = 1; - break; - case 1: - interval = win_count - entry->dccphrx_ccval; - if (interval < 0) - interval += TFRC_WIN_COUNT_LIMIT; - if (interval > 4) - goto found; - break; - } - } - } + struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); + u32 x_recv, p, delta; + u64 fval; - if (unlikely(step == 0)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, packet history " - "contains no data packets!\n", - __FUNCTION__, dccp_role(sk), sk); - return ~0; + if (hc->rx_rtt == 0) { + DCCP_WARN("No RTT estimate available, using fallback RTT\n"); + hc->rx_rtt = DCCP_FALLBACK_RTT; } - if (unlikely(interval == 0)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, Could not find a " - "win_count interval > 0. Defaulting to 1\n", - __FUNCTION__, dccp_role(sk), sk); - interval = 1; + delta = ktime_to_us(net_timedelta(hc->rx_tstamp_last_feedback)); + x_recv = scaled_div32(hc->rx_bytes_recv, delta); + if (x_recv == 0) { /* would also trigger divide-by-zero */ + DCCP_WARN("X_recv==0\n"); + if (hc->rx_x_recv == 0) { + DCCP_BUG("stored value of X_recv is zero"); + return ~0U; + } + x_recv = hc->rx_x_recv; } -found: - rtt = timeval_delta(&tstamp, &tail->dccphrx_tstamp) * 4 / interval; - ccid3_pr_debug("%s, sk=%p, approximated RTT to %uus\n", - dccp_role(sk), sk, rtt); - if (rtt == 0) - rtt = 1; - - dccp_timestamp(sk, &tstamp); - delta = timeval_delta(&tstamp, &hcrx->ccid3hcrx_tstamp_last_feedback); - x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, delta); - - tmp1 = (u64)x_recv * (u64)rtt; - do_div(tmp1,10000000); - tmp2 = (u32)tmp1; - fval = (hcrx->ccid3hcrx_s * 100000) / tmp2; - /* do not alter order above or you will get overflow on 32 bit */ - p = tfrc_calc_x_reverse_lookup(fval); - ccid3_pr_debug("%s, sk=%p, receive rate=%u bytes/s, implied " - "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); - if (p == 0) - return ~0; - else - return 1000000 / p; -} - -static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss) -{ - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - - if (seq_loss != DCCP_MAX_SEQNO + 1 && - list_empty(&hcrx->ccid3hcrx_li_hist)) { - struct dccp_li_hist_entry *li_tail; - - li_tail = dccp_li_hist_interval_new(ccid3_li_hist, - &hcrx->ccid3hcrx_li_hist, - seq_loss, win_loss); - if (li_tail == NULL) - return; - li_tail->dccplih_interval = ccid3_hc_rx_calc_first_li(sk); - } else - LIMIT_NETDEBUG(KERN_WARNING "%s: FIXME: find end of " - "interval\n", __FUNCTION__); -} + fval = scaled_div(hc->rx_s, hc->rx_rtt); + fval = scaled_div32(fval, x_recv); + p = tfrc_calc_x_reverse_lookup(fval); -static void ccid3_hc_rx_detect_loss(struct sock *sk) -{ - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - u8 win_loss; - const u64 seq_loss = dccp_rx_hist_detect_loss(&hcrx->ccid3hcrx_hist, - &hcrx->ccid3hcrx_li_hist, - &win_loss); + ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied " + "loss rate=%u\n", dccp_role(sk), sk, x_recv, p); - ccid3_hc_rx_update_li(sk, seq_loss, win_loss); + return p == 0 ? ~0U : scaled_div(1, p); } static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) { - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - const struct dccp_options_received *opt_recv; - struct dccp_rx_hist_entry *packet; - struct timeval now; - u8 win_count; - u32 p_prev, r_sample, t_elapsed; - int ins; - - BUG_ON(hcrx == NULL || - !(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA || - hcrx->ccid3hcrx_state == TFRC_RSTATE_DATA)); - - opt_recv = &dccp_sk(sk)->dccps_options_received; - - switch (DCCP_SKB_CB(skb)->dccpd_type) { - case DCCP_PKT_ACK: - if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) - return; - case DCCP_PKT_DATAACK: - if (opt_recv->dccpor_timestamp_echo == 0) - break; - p_prev = hcrx->ccid3hcrx_rtt; - dccp_timestamp(sk, &now); - timeval_sub_usecs(&now, opt_recv->dccpor_timestamp_echo * 10); - r_sample = timeval_usecs(&now); - t_elapsed = opt_recv->dccpor_elapsed_time * 10; - - if (unlikely(r_sample <= t_elapsed)) - LIMIT_NETDEBUG(KERN_WARNING "%s: r_sample=%uus, " - "t_elapsed=%uus\n", - __FUNCTION__, r_sample, t_elapsed); - else - r_sample -= t_elapsed; + struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); + enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE; + const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp; + const bool is_data_packet = dccp_data_packet(skb); + + if (unlikely(hc->rx_state == TFRC_RSTATE_NO_DATA)) { + if (is_data_packet) { + const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; + do_feedback = CCID3_FBACK_INITIAL; + ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); + hc->rx_s = payload; + /* + * Not necessary to update rx_bytes_recv here, + * since X_recv = 0 for the first feedback packet (cf. + * RFC 3448, 6.3) -- gerrit + */ + } + goto update_records; + } - if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA) - hcrx->ccid3hcrx_rtt = r_sample; - else - hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 + - r_sample / 10; + if (tfrc_rx_hist_duplicate(&hc->rx_hist, skb)) + return; /* done receiving */ - if (p_prev != hcrx->ccid3hcrx_rtt) - ccid3_pr_debug("%s, New RTT=%luus, elapsed time=%u\n", - dccp_role(sk), hcrx->ccid3hcrx_rtt, - opt_recv->dccpor_elapsed_time); - break; - case DCCP_PKT_DATA: - break; - default: /* We're not interested in other packet types, move along */ - return; + if (is_data_packet) { + const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4; + /* + * Update moving-average of s and the sum of received payload bytes + */ + hc->rx_s = tfrc_ewma(hc->rx_s, payload, 9); + hc->rx_bytes_recv += payload; } - packet = dccp_rx_hist_entry_new(ccid3_rx_hist, sk, opt_recv->dccpor_ndp, - skb, SLAB_ATOMIC); - if (unlikely(packet == NULL)) { - LIMIT_NETDEBUG(KERN_WARNING "%s: %s, sk=%p, Not enough mem to " - "add rx packet to history, consider it lost!\n", - __FUNCTION__, dccp_role(sk), sk); - return; + /* + * Perform loss detection and handle pending losses + */ + if (tfrc_rx_handle_loss(&hc->rx_hist, &hc->rx_li_hist, + skb, ndp, ccid3_first_li, sk)) { + do_feedback = CCID3_FBACK_PARAM_CHANGE; + goto done_receiving; } - win_count = packet->dccphrx_ccval; + if (tfrc_rx_hist_loss_pending(&hc->rx_hist)) + return; /* done receiving */ - ins = dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist, - &hcrx->ccid3hcrx_li_hist, packet); - - if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK) - return; + /* + * Handle data packets: RTT sampling and monitoring p + */ + if (unlikely(!is_data_packet)) + goto update_records; - switch (hcrx->ccid3hcrx_state) { - case TFRC_RSTATE_NO_DATA: - ccid3_pr_debug("%s, sk=%p(%s), skb=%p, sending initial " - "feedback\n", - dccp_role(sk), sk, - dccp_state_name(sk->sk_state), skb); - ccid3_hc_rx_send_feedback(sk); - ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA); - return; - case TFRC_RSTATE_DATA: - hcrx->ccid3hcrx_bytes_recv += skb->len - - dccp_hdr(skb)->dccph_doff * 4; - if (ins != 0) - break; + if (!tfrc_lh_is_initialised(&hc->rx_li_hist)) { + const u32 sample = tfrc_rx_hist_sample_rtt(&hc->rx_hist, skb); + /* + * Empty loss history: no loss so far, hence p stays 0. + * Sample RTT values, since an RTT estimate is required for the + * computation of p when the first loss occurs; RFC 3448, 6.3.1. + */ + if (sample != 0) + hc->rx_rtt = tfrc_ewma(hc->rx_rtt, sample, 9); - dccp_timestamp(sk, &now); - if (timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) >= - hcrx->ccid3hcrx_rtt) { - hcrx->ccid3hcrx_tstamp_last_ack = now; - ccid3_hc_rx_send_feedback(sk); - } - return; - default: - printk(KERN_CRIT "%s: %s, sk=%p, Illegal state (%d)!\n", - __FUNCTION__, dccp_role(sk), sk, hcrx->ccid3hcrx_state); - dump_stack(); - return; + } else if (tfrc_lh_update_i_mean(&hc->rx_li_hist, skb)) { + /* + * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean + * has decreased (resp. p has increased), send feedback now. + */ + do_feedback = CCID3_FBACK_PARAM_CHANGE; } - /* Dealing with packet loss */ - ccid3_pr_debug("%s, sk=%p(%s), data loss! Reacting...\n", - dccp_role(sk), sk, dccp_state_name(sk->sk_state)); + /* + * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3 + */ + if (SUB16(dccp_hdr(skb)->dccph_ccval, hc->rx_last_counter) > 3) + do_feedback = CCID3_FBACK_PERIODIC; - ccid3_hc_rx_detect_loss(sk); - p_prev = hcrx->ccid3hcrx_p; - - /* Calculate loss event rate */ - if (!list_empty(&hcrx->ccid3hcrx_li_hist)) - /* Scaling up by 1000000 as fixed decimal */ - hcrx->ccid3hcrx_p = 1000000 / dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist); +update_records: + tfrc_rx_hist_add_packet(&hc->rx_hist, skb, ndp); - if (hcrx->ccid3hcrx_p > p_prev) { - ccid3_hc_rx_send_feedback(sk); - return; - } +done_receiving: + if (do_feedback) + ccid3_hc_rx_send_feedback(sk, skb, do_feedback); } -static int ccid3_hc_rx_init(struct sock *sk) +static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct ccid3_hc_rx_sock *hcrx; - - ccid3_pr_debug("%s, sk=%p\n", dccp_role(sk), sk); - - dp->dccps_hc_rx_ccid_private = kmalloc(sizeof(*hcrx), gfp_any()); - if (dp->dccps_hc_rx_ccid_private == NULL) - return -ENOMEM; + struct ccid3_hc_rx_sock *hc = ccid_priv(ccid); - hcrx = ccid3_hc_rx_sk(sk); - memset(hcrx, 0, sizeof(*hcrx)); - - if (dp->dccps_packet_size >= TFRC_MIN_PACKET_SIZE && - dp->dccps_packet_size <= TFRC_MAX_PACKET_SIZE) - hcrx->ccid3hcrx_s = dp->dccps_packet_size; - else - hcrx->ccid3hcrx_s = TFRC_STD_PACKET_SIZE; - - hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA; - INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist); - INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist); - dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack); - hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack; - hcrx->ccid3hcrx_rtt = 5000; /* XXX 5ms for now... */ - return 0; + hc->rx_state = TFRC_RSTATE_NO_DATA; + tfrc_lh_init(&hc->rx_li_hist); + return tfrc_rx_hist_alloc(&hc->rx_hist); } static void ccid3_hc_rx_exit(struct sock *sk) { - struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - struct dccp_sock *dp = dccp_sk(sk); - - BUG_ON(hcrx == NULL); - - ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM); - - /* Empty packet history */ - dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist); + struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); - /* Empty loss interval history */ - dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist); - - kfree(dp->dccps_hc_rx_ccid_private); - dp->dccps_hc_rx_ccid_private = NULL; + tfrc_rx_hist_purge(&hc->rx_hist); + tfrc_lh_cleanup(&hc->rx_li_hist); } static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info) { - const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); - - /* Listen socks doesn't have a private CCID block */ - if (sk->sk_state == DCCP_LISTEN) - return; - - BUG_ON(hcrx == NULL); - - info->tcpi_ca_state = hcrx->ccid3hcrx_state; - info->tcpi_options |= TCPI_OPT_TIMESTAMPS; - info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt; -} - -static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info) -{ - const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - - /* Listen socks doesn't have a private CCID block */ - if (sk->sk_state == DCCP_LISTEN) - return; - - BUG_ON(hctx == NULL); - - info->tcpi_rto = hctx->ccid3hctx_t_rto; - info->tcpi_rtt = hctx->ccid3hctx_rtt; + info->tcpi_ca_state = ccid3_hc_rx_sk(sk)->rx_state; + info->tcpi_options |= TCPI_OPT_TIMESTAMPS; + info->tcpi_rcv_rtt = ccid3_hc_rx_sk(sk)->rx_rtt; } static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, u32 __user *optval, int __user *optlen) { - const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk); + const struct ccid3_hc_rx_sock *hc = ccid3_hc_rx_sk(sk); + struct tfrc_rx_info rx_info; const void *val; - - /* Listen socks doesn't have a private CCID block */ - if (sk->sk_state == DCCP_LISTEN) - return -EINVAL; switch (optname) { case DCCP_SOCKOPT_CCID_RX_INFO: - if (len < sizeof(hcrx->ccid3hcrx_tfrc)) + if (len < sizeof(rx_info)) return -EINVAL; - len = sizeof(hcrx->ccid3hcrx_tfrc); - val = &hcrx->ccid3hcrx_tfrc; + rx_info.tfrcrx_x_recv = hc->rx_x_recv; + rx_info.tfrcrx_rtt = hc->rx_rtt; + rx_info.tfrcrx_p = tfrc_invert_loss_event_rate(hc->rx_pinv); + len = sizeof(rx_info); + val = &rx_info; break; default: return -ENOPROTOOPT; @@ -1147,46 +843,17 @@ static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len, return 0; } -static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len, - u32 __user *optval, int __user *optlen) -{ - const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); - const void *val; - - /* Listen socks doesn't have a private CCID block */ - if (sk->sk_state == DCCP_LISTEN) - return -EINVAL; - - switch (optname) { - case DCCP_SOCKOPT_CCID_TX_INFO: - if (len < sizeof(hctx->ccid3hctx_tfrc)) - return -EINVAL; - len = sizeof(hctx->ccid3hctx_tfrc); - val = &hctx->ccid3hctx_tfrc; - break; - default: - return -ENOPROTOOPT; - } - - if (put_user(len, optlen) || copy_to_user(optval, val, len)) - return -EFAULT; - - return 0; -} - -static struct ccid ccid3 = { - .ccid_id = 3, - .ccid_name = "ccid3", - .ccid_owner = THIS_MODULE, - .ccid_init = ccid3_init, - .ccid_exit = ccid3_exit, +struct ccid_operations ccid3_ops = { + .ccid_id = DCCPC_CCID3, + .ccid_name = "TCP-Friendly Rate Control", + .ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock), .ccid_hc_tx_init = ccid3_hc_tx_init, .ccid_hc_tx_exit = ccid3_hc_tx_exit, .ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet, .ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent, .ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv, - .ccid_hc_tx_insert_options = ccid3_hc_tx_insert_options, .ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options, + .ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock), .ccid_hc_rx_init = ccid3_hc_rx_init, .ccid_hc_rx_exit = ccid3_hc_rx_exit, .ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options, @@ -1196,75 +863,8 @@ static struct ccid ccid3 = { .ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt, .ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt, }; - -module_param(ccid3_debug, int, 0444); -MODULE_PARM_DESC(ccid3_debug, "Enable debug messages"); - -static __init int ccid3_module_init(void) -{ - int rc = -ENOBUFS; - - ccid3_rx_hist = dccp_rx_hist_new("ccid3"); - if (ccid3_rx_hist == NULL) - goto out; - - ccid3_tx_hist = dccp_tx_hist_new("ccid3"); - if (ccid3_tx_hist == NULL) - goto out_free_rx; - - ccid3_li_hist = dccp_li_hist_new("ccid3"); - if (ccid3_li_hist == NULL) - goto out_free_tx; - - rc = ccid_register(&ccid3); - if (rc != 0) - goto out_free_loss_interval_history; -out: - return rc; - -out_free_loss_interval_history: - dccp_li_hist_delete(ccid3_li_hist); - ccid3_li_hist = NULL; -out_free_tx: - dccp_tx_hist_delete(ccid3_tx_hist); - ccid3_tx_hist = NULL; -out_free_rx: - dccp_rx_hist_delete(ccid3_rx_hist); - ccid3_rx_hist = NULL; - goto out; -} -module_init(ccid3_module_init); -static __exit void ccid3_module_exit(void) -{ -#ifdef CONFIG_IP_DCCP_UNLOAD_HACK - /* - * Hack to use while developing, so that we get rid of the control - * sock, that is what keeps a refcount on dccp.ko -acme - */ - extern void dccp_ctl_sock_exit(void); - - dccp_ctl_sock_exit(); +#ifdef CONFIG_IP_DCCP_CCID3_DEBUG +module_param(ccid3_debug, bool, 0644); +MODULE_PARM_DESC(ccid3_debug, "Enable CCID-3 debug messages"); #endif - ccid_unregister(&ccid3); - - if (ccid3_tx_hist != NULL) { - dccp_tx_hist_delete(ccid3_tx_hist); - ccid3_tx_hist = NULL; - } - if (ccid3_rx_hist != NULL) { - dccp_rx_hist_delete(ccid3_rx_hist); - ccid3_rx_hist = NULL; - } - if (ccid3_li_hist != NULL) { - dccp_li_hist_delete(ccid3_li_hist); - ccid3_li_hist = NULL; - } -} -module_exit(ccid3_module_exit); - -MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, " - "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); -MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("net-dccp-ccid-3"); diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h index 0bde4583d09..1a9933c2967 100644 --- a/net/dccp/ccids/ccid3.h +++ b/net/dccp/ccids/ccid3.h @@ -1,13 +1,12 @@ /* - * net/dccp/ccids/ccid3.h - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK * * An implementation of the DCCP protocol * * This code has been developed by the University of Waikato WAND * research group. For further information please see http://www.wand.net.nz/ - * or e-mail Ian McDonald - iam4@cs.waikato.ac.nz + * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz * * This code also uses code from Lulea University, rereleased as GPL by its * authors: @@ -36,28 +35,31 @@ #ifndef _DCCP_CCID3_H_ #define _DCCP_CCID3_H_ -#include <linux/config.h> +#include <linux/ktime.h> #include <linux/list.h> -#include <linux/time.h> #include <linux/types.h> #include <linux/tfrc.h> +#include "lib/tfrc.h" +#include "../ccid.h" -#define TFRC_MIN_PACKET_SIZE 16 -#define TFRC_STD_PACKET_SIZE 256 -#define TFRC_MAX_PACKET_SIZE 65535 - -/* Two seconds as per CCID3 spec */ +/* Two seconds as per RFC 5348, 4.2 */ #define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC) -#define TFRC_INITIAL_IPI (USEC_PER_SEC / 4) - -/* In usecs - half the scheduling granularity as per RFC3448 4.6 */ -#define TFRC_OPSYS_HALF_TIME_GRAN (USEC_PER_SEC / (2 * HZ)) +/* Parameter t_mbi from [RFC 3448, 4.3]: backoff interval in seconds */ +#define TFRC_T_MBI 64 -/* In seconds */ -#define TFRC_MAX_BACK_OFF_TIME 64 - -#define TFRC_SMALLEST_P 40 +/* + * The t_delta parameter (RFC 5348, 8.3): delays of less than %USEC_PER_MSEC are + * rounded down to 0, since sk_reset_timer() here uses millisecond granularity. + * Hence we can use a constant t_delta = %USEC_PER_MSEC when HZ >= 500. A coarse + * resolution of HZ < 500 means that the error is below one timer tick (t_gran) + * when using the constant t_delta = t_gran / 2 = %USEC_PER_SEC / (2 * HZ). + */ +#if (HZ >= 500) +# define TFRC_T_DELTA USEC_PER_MSEC +#else +# define TFRC_T_DELTA (USEC_PER_SEC / (2 * HZ)) +#endif enum ccid3_options { TFRC_OPT_LOSS_EVENT_RATE = 192, @@ -65,82 +67,94 @@ enum ccid3_options { TFRC_OPT_RECEIVE_RATE = 194, }; -struct ccid3_options_received { - u64 ccid3or_seqno:48, - ccid3or_loss_intervals_idx:16; - u16 ccid3or_loss_intervals_len; - u32 ccid3or_loss_event_rate; - u32 ccid3or_receive_rate; +/* TFRC sender states */ +enum ccid3_hc_tx_states { + TFRC_SSTATE_NO_SENT = 1, + TFRC_SSTATE_NO_FBACK, + TFRC_SSTATE_FBACK, }; -/** struct ccid3_hc_tx_sock - CCID3 sender half connection sock - * - * @ccid3hctx_state - Sender state - * @ccid3hctx_x - Current sending rate - * @ccid3hctx_x_recv - Receive rate - * @ccid3hctx_x_calc - Calculated send (?) rate - * @ccid3hctx_s - Packet size - * @ccid3hctx_rtt - Estimate of current round trip time in usecs - * @@ccid3hctx_p - Current loss event rate (0-1) scaled by 1000000 - * @ccid3hctx_last_win_count - Last window counter sent - * @ccid3hctx_t_last_win_count - Timestamp of earliest packet - * with last_win_count value sent - * @ccid3hctx_no_feedback_timer - Handle to no feedback timer - * @ccid3hctx_idle - FIXME - * @ccid3hctx_t_ld - Time last doubled during slow start - * @ccid3hctx_t_nom - Nominal send time of next packet - * @ccid3hctx_t_ipi - Interpacket (send) interval - * @ccid3hctx_delta - Send timer delta - * @ccid3hctx_hist - Packet history - */ +/** + * struct ccid3_hc_tx_sock - CCID3 sender half-connection socket + * @tx_x: Current sending rate in 64 * bytes per second + * @tx_x_recv: Receive rate in 64 * bytes per second + * @tx_x_calc: Calculated rate in bytes per second + * @tx_rtt: Estimate of current round trip time in usecs + * @tx_p: Current loss event rate (0-1) scaled by 1000000 + * @tx_s: Packet size in bytes + * @tx_t_rto: Nofeedback Timer setting in usecs + * @tx_t_ipi: Interpacket (send) interval (RFC 3448, 4.6) in usecs + * @tx_state: Sender state, one of %ccid3_hc_tx_states + * @tx_last_win_count: Last window counter sent + * @tx_t_last_win_count: Timestamp of earliest packet + * with last_win_count value sent + * @tx_no_feedback_timer: Handle to no feedback timer + * @tx_t_ld: Time last doubled during slow start + * @tx_t_nom: Nominal send time of next packet + * @tx_hist: Packet history + */ struct ccid3_hc_tx_sock { - struct tfrc_tx_info ccid3hctx_tfrc; -#define ccid3hctx_x ccid3hctx_tfrc.tfrctx_x -#define ccid3hctx_x_recv ccid3hctx_tfrc.tfrctx_x_recv -#define ccid3hctx_x_calc ccid3hctx_tfrc.tfrctx_x_calc -#define ccid3hctx_rtt ccid3hctx_tfrc.tfrctx_rtt -#define ccid3hctx_p ccid3hctx_tfrc.tfrctx_p -#define ccid3hctx_t_rto ccid3hctx_tfrc.tfrctx_rto -#define ccid3hctx_t_ipi ccid3hctx_tfrc.tfrctx_ipi - u16 ccid3hctx_s; - u8 ccid3hctx_state; - u8 ccid3hctx_last_win_count; - u8 ccid3hctx_idle; - struct timeval ccid3hctx_t_last_win_count; - struct timer_list ccid3hctx_no_feedback_timer; - struct timeval ccid3hctx_t_ld; - struct timeval ccid3hctx_t_nom; - u32 ccid3hctx_delta; - struct list_head ccid3hctx_hist; - struct ccid3_options_received ccid3hctx_options_received; -}; - -struct ccid3_hc_rx_sock { - struct tfrc_rx_info ccid3hcrx_tfrc; -#define ccid3hcrx_x_recv ccid3hcrx_tfrc.tfrcrx_x_recv -#define ccid3hcrx_rtt ccid3hcrx_tfrc.tfrcrx_rtt -#define ccid3hcrx_p ccid3hcrx_tfrc.tfrcrx_p - u64 ccid3hcrx_seqno_last_counter:48, - ccid3hcrx_state:8, - ccid3hcrx_last_counter:4; - u32 ccid3hcrx_bytes_recv; - struct timeval ccid3hcrx_tstamp_last_feedback; - struct timeval ccid3hcrx_tstamp_last_ack; - struct list_head ccid3hcrx_hist; - struct list_head ccid3hcrx_li_hist; - u16 ccid3hcrx_s; - u32 ccid3hcrx_pinv; - u32 ccid3hcrx_elapsed_time; + u64 tx_x; + u64 tx_x_recv; + u32 tx_x_calc; + u32 tx_rtt; + u32 tx_p; + u32 tx_t_rto; + u32 tx_t_ipi; + u16 tx_s; + enum ccid3_hc_tx_states tx_state:8; + u8 tx_last_win_count; + ktime_t tx_t_last_win_count; + struct timer_list tx_no_feedback_timer; + ktime_t tx_t_ld; + ktime_t tx_t_nom; + struct tfrc_tx_hist_entry *tx_hist; }; static inline struct ccid3_hc_tx_sock *ccid3_hc_tx_sk(const struct sock *sk) { - return dccp_sk(sk)->dccps_hc_tx_ccid_private; + struct ccid3_hc_tx_sock *hctx = ccid_priv(dccp_sk(sk)->dccps_hc_tx_ccid); + BUG_ON(hctx == NULL); + return hctx; } +/* TFRC receiver states */ +enum ccid3_hc_rx_states { + TFRC_RSTATE_NO_DATA = 1, + TFRC_RSTATE_DATA, +}; + +/** + * struct ccid3_hc_rx_sock - CCID3 receiver half-connection socket + * @rx_last_counter: Tracks window counter (RFC 4342, 8.1) + * @rx_state: Receiver state, one of %ccid3_hc_rx_states + * @rx_bytes_recv: Total sum of DCCP payload bytes + * @rx_x_recv: Receiver estimate of send rate (RFC 3448, sec. 4.3) + * @rx_rtt: Receiver estimate of RTT + * @rx_tstamp_last_feedback: Time at which last feedback was sent + * @rx_hist: Packet history (loss detection + RTT sampling) + * @rx_li_hist: Loss Interval database + * @rx_s: Received packet size in bytes + * @rx_pinv: Inverse of Loss Event Rate (RFC 4342, sec. 8.5) + */ +struct ccid3_hc_rx_sock { + u8 rx_last_counter:4; + enum ccid3_hc_rx_states rx_state:8; + u32 rx_bytes_recv; + u32 rx_x_recv; + u32 rx_rtt; + ktime_t rx_tstamp_last_feedback; + struct tfrc_rx_hist rx_hist; + struct tfrc_loss_hist rx_li_hist; + u16 rx_s; +#define rx_pinv rx_li_hist.i_mean +}; + static inline struct ccid3_hc_rx_sock *ccid3_hc_rx_sk(const struct sock *sk) { - return dccp_sk(sk)->dccps_hc_rx_ccid_private; + struct ccid3_hc_rx_sock *hcrx = ccid_priv(dccp_sk(sk)->dccps_hc_rx_ccid); + BUG_ON(hcrx == NULL); + return hcrx; } #endif /* _DCCP_CCID3_H_ */ diff --git a/net/dccp/ccids/lib/Makefile b/net/dccp/ccids/lib/Makefile deleted file mode 100644 index 5f940a6cbac..00000000000 --- a/net/dccp/ccids/lib/Makefile +++ /dev/null @@ -1,3 +0,0 @@ -obj-$(CONFIG_IP_DCCP_TFRC_LIB) += dccp_tfrc_lib.o - -dccp_tfrc_lib-y := loss_interval.o packet_history.o tfrc_equation.o diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c index 4c01a54143a..57f9fd78c4d 100644 --- a/net/dccp/ccids/lib/loss_interval.c +++ b/net/dccp/ccids/lib/loss_interval.c @@ -1,8 +1,7 @@ /* - * net/dccp/ccids/lib/loss_interval.c - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> * * This program is free software; you can redistribute it and/or modify @@ -10,135 +9,177 @@ * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ +#include <net/sock.h> +#include "tfrc.h" -#include <linux/config.h> -#include <linux/module.h> - -#include "loss_interval.h" +static struct kmem_cache *tfrc_lh_slab __read_mostly; +/* Loss Interval weights from [RFC 3448, 5.4], scaled by 10 */ +static const int tfrc_lh_weights[NINTERVAL] = { 10, 10, 10, 10, 8, 6, 4, 2 }; -struct dccp_li_hist *dccp_li_hist_new(const char *name) +/* implements LIFO semantics on the array */ +static inline u8 LIH_INDEX(const u8 ctr) { - struct dccp_li_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC); - static const char dccp_li_hist_mask[] = "li_hist_%s"; - char *slab_name; - - if (hist == NULL) - goto out; - - slab_name = kmalloc(strlen(name) + sizeof(dccp_li_hist_mask) - 1, - GFP_ATOMIC); - if (slab_name == NULL) - goto out_free_hist; - - sprintf(slab_name, dccp_li_hist_mask, name); - hist->dccplih_slab = kmem_cache_create(slab_name, - sizeof(struct dccp_li_hist_entry), - 0, SLAB_HWCACHE_ALIGN, - NULL, NULL); - if (hist->dccplih_slab == NULL) - goto out_free_slab_name; -out: - return hist; -out_free_slab_name: - kfree(slab_name); -out_free_hist: - kfree(hist); - hist = NULL; - goto out; + return LIH_SIZE - 1 - (ctr % LIH_SIZE); } -EXPORT_SYMBOL_GPL(dccp_li_hist_new); +/* the `counter' index always points at the next entry to be populated */ +static inline struct tfrc_loss_interval *tfrc_lh_peek(struct tfrc_loss_hist *lh) +{ + return lh->counter ? lh->ring[LIH_INDEX(lh->counter - 1)] : NULL; +} -void dccp_li_hist_delete(struct dccp_li_hist *hist) +/* given i with 0 <= i <= k, return I_i as per the rfc3448bis notation */ +static inline u32 tfrc_lh_get_interval(struct tfrc_loss_hist *lh, const u8 i) { - const char* name = kmem_cache_name(hist->dccplih_slab); + BUG_ON(i >= lh->counter); + return lh->ring[LIH_INDEX(lh->counter - i - 1)]->li_length; +} - kmem_cache_destroy(hist->dccplih_slab); - kfree(name); - kfree(hist); +/* + * On-demand allocation and de-allocation of entries + */ +static struct tfrc_loss_interval *tfrc_lh_demand_next(struct tfrc_loss_hist *lh) +{ + if (lh->ring[LIH_INDEX(lh->counter)] == NULL) + lh->ring[LIH_INDEX(lh->counter)] = kmem_cache_alloc(tfrc_lh_slab, + GFP_ATOMIC); + return lh->ring[LIH_INDEX(lh->counter)]; } -EXPORT_SYMBOL_GPL(dccp_li_hist_delete); +void tfrc_lh_cleanup(struct tfrc_loss_hist *lh) +{ + if (!tfrc_lh_is_initialised(lh)) + return; + + for (lh->counter = 0; lh->counter < LIH_SIZE; lh->counter++) + if (lh->ring[LIH_INDEX(lh->counter)] != NULL) { + kmem_cache_free(tfrc_lh_slab, + lh->ring[LIH_INDEX(lh->counter)]); + lh->ring[LIH_INDEX(lh->counter)] = NULL; + } +} -void dccp_li_hist_purge(struct dccp_li_hist *hist, struct list_head *list) +static void tfrc_lh_calc_i_mean(struct tfrc_loss_hist *lh) { - struct dccp_li_hist_entry *entry, *next; + u32 i_i, i_tot0 = 0, i_tot1 = 0, w_tot = 0; + int i, k = tfrc_lh_length(lh) - 1; /* k is as in rfc3448bis, 5.4 */ + + if (k <= 0) + return; + + for (i = 0; i <= k; i++) { + i_i = tfrc_lh_get_interval(lh, i); - list_for_each_entry_safe(entry, next, list, dccplih_node) { - list_del_init(&entry->dccplih_node); - kmem_cache_free(hist->dccplih_slab, entry); + if (i < k) { + i_tot0 += i_i * tfrc_lh_weights[i]; + w_tot += tfrc_lh_weights[i]; + } + if (i > 0) + i_tot1 += i_i * tfrc_lh_weights[i-1]; } -} -EXPORT_SYMBOL_GPL(dccp_li_hist_purge); + lh->i_mean = max(i_tot0, i_tot1) / w_tot; +} -/* Weights used to calculate loss event rate */ -/* - * These are integers as per section 8 of RFC3448. We can then divide by 4 * - * when we use it. +/** + * tfrc_lh_update_i_mean - Update the `open' loss interval I_0 + * For recomputing p: returns `true' if p > p_prev <=> 1/p < 1/p_prev */ -static const int dccp_li_hist_w[DCCP_LI_HIST_IVAL_F_LENGTH] = { - 4, 4, 4, 4, 3, 2, 1, 1, -}; - -u32 dccp_li_hist_calc_i_mean(struct list_head *list) +u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb) { - struct dccp_li_hist_entry *li_entry, *li_next; - int i = 0; - u32 i_tot; - u32 i_tot0 = 0; - u32 i_tot1 = 0; - u32 w_tot = 0; - - list_for_each_entry_safe(li_entry, li_next, list, dccplih_node) { - if (i < DCCP_LI_HIST_IVAL_F_LENGTH) { - i_tot0 += li_entry->dccplih_interval * dccp_li_hist_w[i]; - w_tot += dccp_li_hist_w[i]; - } + struct tfrc_loss_interval *cur = tfrc_lh_peek(lh); + u32 old_i_mean = lh->i_mean; + s64 len; - if (i != 0) - i_tot1 += li_entry->dccplih_interval * dccp_li_hist_w[i - 1]; + if (cur == NULL) /* not initialised */ + return 0; - if (++i > DCCP_LI_HIST_IVAL_F_LENGTH) - break; - } + len = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq) + 1; - if (i != DCCP_LI_HIST_IVAL_F_LENGTH) + if (len - (s64)cur->li_length <= 0) /* duplicate or reordered */ return 0; - i_tot = max(i_tot0, i_tot1); + if (SUB16(dccp_hdr(skb)->dccph_ccval, cur->li_ccval) > 4) + /* + * Implements RFC 4342, 10.2: + * If a packet S (skb) exists whose seqno comes `after' the one + * starting the current loss interval (cur) and if the modulo-16 + * distance from C(cur) to C(S) is greater than 4, consider all + * subsequent packets as belonging to a new loss interval. This + * test is necessary since CCVal may wrap between intervals. + */ + cur->li_is_closed = 1; + + if (tfrc_lh_length(lh) == 1) /* due to RFC 3448, 6.3.1 */ + return 0; - /* FIXME: Why do we do this? -Ian McDonald */ - if (i_tot * 4 < w_tot) - i_tot = w_tot * 4; + cur->li_length = len; + tfrc_lh_calc_i_mean(lh); - return i_tot * 4 / w_tot; + return lh->i_mean < old_i_mean; } -EXPORT_SYMBOL_GPL(dccp_li_hist_calc_i_mean); +/* Determine if `new_loss' does begin a new loss interval [RFC 4342, 10.2] */ +static inline u8 tfrc_lh_is_new_loss(struct tfrc_loss_interval *cur, + struct tfrc_rx_hist_entry *new_loss) +{ + return dccp_delta_seqno(cur->li_seqno, new_loss->tfrchrx_seqno) > 0 && + (cur->li_is_closed || SUB16(new_loss->tfrchrx_ccval, cur->li_ccval) > 4); +} -struct dccp_li_hist_entry *dccp_li_hist_interval_new(struct dccp_li_hist *hist, - struct list_head *list, - const u64 seq_loss, - const u8 win_loss) +/** + * tfrc_lh_interval_add - Insert new record into the Loss Interval database + * @lh: Loss Interval database + * @rh: Receive history containing a fresh loss event + * @calc_first_li: Caller-dependent routine to compute length of first interval + * @sk: Used by @calc_first_li in caller-specific way (subtyping) + * + * Updates I_mean and returns 1 if a new interval has in fact been added to @lh. + */ +int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh, + u32 (*calc_first_li)(struct sock *), struct sock *sk) { - struct dccp_li_hist_entry *tail = NULL, *entry; - int i; - - for (i = 0; i <= DCCP_LI_HIST_IVAL_F_LENGTH; ++i) { - entry = dccp_li_hist_entry_new(hist, SLAB_ATOMIC); - if (entry == NULL) { - dccp_li_hist_purge(hist, list); - return NULL; - } - if (tail == NULL) - tail = entry; - list_add(&entry->dccplih_node, list); + struct tfrc_loss_interval *cur = tfrc_lh_peek(lh), *new; + + if (cur != NULL && !tfrc_lh_is_new_loss(cur, tfrc_rx_hist_loss_prev(rh))) + return 0; + + new = tfrc_lh_demand_next(lh); + if (unlikely(new == NULL)) { + DCCP_CRIT("Cannot allocate/add loss record."); + return 0; + } + + new->li_seqno = tfrc_rx_hist_loss_prev(rh)->tfrchrx_seqno; + new->li_ccval = tfrc_rx_hist_loss_prev(rh)->tfrchrx_ccval; + new->li_is_closed = 0; + + if (++lh->counter == 1) + lh->i_mean = new->li_length = (*calc_first_li)(sk); + else { + cur->li_length = dccp_delta_seqno(cur->li_seqno, new->li_seqno); + new->li_length = dccp_delta_seqno(new->li_seqno, + tfrc_rx_hist_last_rcv(rh)->tfrchrx_seqno) + 1; + if (lh->counter > (2*LIH_SIZE)) + lh->counter -= LIH_SIZE; + + tfrc_lh_calc_i_mean(lh); } + return 1; +} - entry->dccplih_seqno = seq_loss; - entry->dccplih_win_count = win_loss; - return tail; +int __init tfrc_li_init(void) +{ + tfrc_lh_slab = kmem_cache_create("tfrc_li_hist", + sizeof(struct tfrc_loss_interval), 0, + SLAB_HWCACHE_ALIGN, NULL); + return tfrc_lh_slab == NULL ? -ENOBUFS : 0; } -EXPORT_SYMBOL_GPL(dccp_li_hist_interval_new); +void tfrc_li_exit(void) +{ + if (tfrc_lh_slab != NULL) { + kmem_cache_destroy(tfrc_lh_slab); + tfrc_lh_slab = NULL; + } +} diff --git a/net/dccp/ccids/lib/loss_interval.h b/net/dccp/ccids/lib/loss_interval.h index 417d9d82df3..57f631a86cc 100644 --- a/net/dccp/ccids/lib/loss_interval.h +++ b/net/dccp/ccids/lib/loss_interval.h @@ -1,10 +1,9 @@ #ifndef _DCCP_LI_HIST_ #define _DCCP_LI_HIST_ /* - * net/dccp/ccids/lib/loss_interval.h - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz> * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> * * This program is free software; you can redistribute it and/or modify it @@ -12,50 +11,63 @@ * Software Foundation; either version 2 of the License, or (at your option) * any later version. */ - -#include <linux/config.h> +#include <linux/ktime.h> #include <linux/list.h> #include <linux/slab.h> -#include <linux/time.h> -#define DCCP_LI_HIST_IVAL_F_LENGTH 8 +/* + * Number of loss intervals (RFC 4342, 8.6.1). The history size is one more than + * NINTERVAL, since the `open' interval I_0 is always stored as the first entry. + */ +#define NINTERVAL 8 +#define LIH_SIZE (NINTERVAL + 1) -struct dccp_li_hist { - kmem_cache_t *dccplih_slab; +/** + * tfrc_loss_interval - Loss history record for TFRC-based protocols + * @li_seqno: Highest received seqno before the start of loss + * @li_ccval: The CCVal belonging to @li_seqno + * @li_is_closed: Whether @li_seqno is older than 1 RTT + * @li_length: Loss interval sequence length + */ +struct tfrc_loss_interval { + u64 li_seqno:48, + li_ccval:4, + li_is_closed:1; + u32 li_length; }; -extern struct dccp_li_hist *dccp_li_hist_new(const char *name); -extern void dccp_li_hist_delete(struct dccp_li_hist *hist); - -struct dccp_li_hist_entry { - struct list_head dccplih_node; - u64 dccplih_seqno:48, - dccplih_win_count:4; - u32 dccplih_interval; +/** + * tfrc_loss_hist - Loss record database + * @ring: Circular queue managed in LIFO manner + * @counter: Current count of entries (can be more than %LIH_SIZE) + * @i_mean: Current Average Loss Interval [RFC 3448, 5.4] + */ +struct tfrc_loss_hist { + struct tfrc_loss_interval *ring[LIH_SIZE]; + u8 counter; + u32 i_mean; }; -static inline struct dccp_li_hist_entry * - dccp_li_hist_entry_new(struct dccp_li_hist *hist, - const gfp_t prio) +static inline void tfrc_lh_init(struct tfrc_loss_hist *lh) +{ + memset(lh, 0, sizeof(struct tfrc_loss_hist)); +} + +static inline u8 tfrc_lh_is_initialised(struct tfrc_loss_hist *lh) { - return kmem_cache_alloc(hist->dccplih_slab, prio); + return lh->counter > 0; } -static inline void dccp_li_hist_entry_delete(struct dccp_li_hist *hist, - struct dccp_li_hist_entry *entry) +static inline u8 tfrc_lh_length(struct tfrc_loss_hist *lh) { - if (entry != NULL) - kmem_cache_free(hist->dccplih_slab, entry); + return min(lh->counter, (u8)LIH_SIZE); } -extern void dccp_li_hist_purge(struct dccp_li_hist *hist, - struct list_head *list); +struct tfrc_rx_hist; -extern u32 dccp_li_hist_calc_i_mean(struct list_head *list); +int tfrc_lh_interval_add(struct tfrc_loss_hist *, struct tfrc_rx_hist *, + u32 (*first_li)(struct sock *), struct sock *); +u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *); +void tfrc_lh_cleanup(struct tfrc_loss_hist *lh); -extern struct dccp_li_hist_entry * - dccp_li_hist_interval_new(struct dccp_li_hist *hist, - struct list_head *list, - const u64 seq_loss, - const u8 win_loss); #endif /* _DCCP_LI_HIST_ */ diff --git a/net/dccp/ccids/lib/packet_history.c b/net/dccp/ccids/lib/packet_history.c index d3f9d205383..08df7a3acb3 100644 --- a/net/dccp/ccids/lib/packet_history.c +++ b/net/dccp/ccids/lib/packet_history.c @@ -1,13 +1,12 @@ /* - * net/dccp/packet_history.h - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand. * * An implementation of the DCCP protocol * * This code has been developed by the University of Waikato WAND * research group. For further information please see http://www.wand.net.nz/ - * or e-mail Ian McDonald - iam4@cs.waikato.ac.nz + * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz * * This code also uses code from Lulea University, rereleased as GPL by its * authors: @@ -34,365 +33,417 @@ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include <linux/config.h> -#include <linux/module.h> #include <linux/string.h> - +#include <linux/slab.h> #include "packet_history.h" +#include "../../dccp.h" -struct dccp_rx_hist *dccp_rx_hist_new(const char *name) +/* + * Transmitter History Routines + */ +static struct kmem_cache *tfrc_tx_hist_slab; + +int __init tfrc_tx_packet_history_init(void) { - struct dccp_rx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC); - static const char dccp_rx_hist_mask[] = "rx_hist_%s"; - char *slab_name; - - if (hist == NULL) - goto out; - - slab_name = kmalloc(strlen(name) + sizeof(dccp_rx_hist_mask) - 1, - GFP_ATOMIC); - if (slab_name == NULL) - goto out_free_hist; - - sprintf(slab_name, dccp_rx_hist_mask, name); - hist->dccprxh_slab = kmem_cache_create(slab_name, - sizeof(struct dccp_rx_hist_entry), - 0, SLAB_HWCACHE_ALIGN, - NULL, NULL); - if (hist->dccprxh_slab == NULL) - goto out_free_slab_name; -out: - return hist; -out_free_slab_name: - kfree(slab_name); -out_free_hist: - kfree(hist); - hist = NULL; - goto out; + tfrc_tx_hist_slab = kmem_cache_create("tfrc_tx_hist", + sizeof(struct tfrc_tx_hist_entry), + 0, SLAB_HWCACHE_ALIGN, NULL); + return tfrc_tx_hist_slab == NULL ? -ENOBUFS : 0; } -EXPORT_SYMBOL_GPL(dccp_rx_hist_new); +void tfrc_tx_packet_history_exit(void) +{ + if (tfrc_tx_hist_slab != NULL) { + kmem_cache_destroy(tfrc_tx_hist_slab); + tfrc_tx_hist_slab = NULL; + } +} + +int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno) +{ + struct tfrc_tx_hist_entry *entry = kmem_cache_alloc(tfrc_tx_hist_slab, gfp_any()); + + if (entry == NULL) + return -ENOBUFS; + entry->seqno = seqno; + entry->stamp = ktime_get_real(); + entry->next = *headp; + *headp = entry; + return 0; +} -void dccp_rx_hist_delete(struct dccp_rx_hist *hist) +void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp) { - const char* name = kmem_cache_name(hist->dccprxh_slab); + struct tfrc_tx_hist_entry *head = *headp; + + while (head != NULL) { + struct tfrc_tx_hist_entry *next = head->next; - kmem_cache_destroy(hist->dccprxh_slab); - kfree(name); - kfree(hist); + kmem_cache_free(tfrc_tx_hist_slab, head); + head = next; + } + + *headp = NULL; } -EXPORT_SYMBOL_GPL(dccp_rx_hist_delete); +/* + * Receiver History Routines + */ +static struct kmem_cache *tfrc_rx_hist_slab; -void dccp_rx_hist_purge(struct dccp_rx_hist *hist, struct list_head *list) +int __init tfrc_rx_packet_history_init(void) { - struct dccp_rx_hist_entry *entry, *next; + tfrc_rx_hist_slab = kmem_cache_create("tfrc_rxh_cache", + sizeof(struct tfrc_rx_hist_entry), + 0, SLAB_HWCACHE_ALIGN, NULL); + return tfrc_rx_hist_slab == NULL ? -ENOBUFS : 0; +} - list_for_each_entry_safe(entry, next, list, dccphrx_node) { - list_del_init(&entry->dccphrx_node); - kmem_cache_free(hist->dccprxh_slab, entry); +void tfrc_rx_packet_history_exit(void) +{ + if (tfrc_rx_hist_slab != NULL) { + kmem_cache_destroy(tfrc_rx_hist_slab); + tfrc_rx_hist_slab = NULL; } } -EXPORT_SYMBOL_GPL(dccp_rx_hist_purge); +static inline void tfrc_rx_hist_entry_from_skb(struct tfrc_rx_hist_entry *entry, + const struct sk_buff *skb, + const u64 ndp) +{ + const struct dccp_hdr *dh = dccp_hdr(skb); + + entry->tfrchrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq; + entry->tfrchrx_ccval = dh->dccph_ccval; + entry->tfrchrx_type = dh->dccph_type; + entry->tfrchrx_ndp = ndp; + entry->tfrchrx_tstamp = ktime_get_real(); +} -struct dccp_rx_hist_entry * - dccp_rx_hist_find_data_packet(const struct list_head *list) +void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h, + const struct sk_buff *skb, + const u64 ndp) { - struct dccp_rx_hist_entry *entry, *packet = NULL; + struct tfrc_rx_hist_entry *entry = tfrc_rx_hist_last_rcv(h); - list_for_each_entry(entry, list, dccphrx_node) - if (entry->dccphrx_type == DCCP_PKT_DATA || - entry->dccphrx_type == DCCP_PKT_DATAACK) { - packet = entry; - break; - } + tfrc_rx_hist_entry_from_skb(entry, skb, ndp); +} - return packet; +/* has the packet contained in skb been seen before? */ +int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb) +{ + const u64 seq = DCCP_SKB_CB(skb)->dccpd_seq; + int i; + + if (dccp_delta_seqno(tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, seq) <= 0) + return 1; + + for (i = 1; i <= h->loss_count; i++) + if (tfrc_rx_hist_entry(h, i)->tfrchrx_seqno == seq) + return 1; + + return 0; } -EXPORT_SYMBOL_GPL(dccp_rx_hist_find_data_packet); +static void tfrc_rx_hist_swap(struct tfrc_rx_hist *h, const u8 a, const u8 b) +{ + const u8 idx_a = tfrc_rx_hist_index(h, a), + idx_b = tfrc_rx_hist_index(h, b); + struct tfrc_rx_hist_entry *tmp = h->ring[idx_a]; + + h->ring[idx_a] = h->ring[idx_b]; + h->ring[idx_b] = tmp; +} -int dccp_rx_hist_add_packet(struct dccp_rx_hist *hist, - struct list_head *rx_list, - struct list_head *li_list, - struct dccp_rx_hist_entry *packet) +/* + * Private helper functions for loss detection. + * + * In the descriptions, `Si' refers to the sequence number of entry number i, + * whose NDP count is `Ni' (lower case is used for variables). + * Note: All __xxx_loss functions expect that a test against duplicates has been + * performed already: the seqno of the skb must not be less than the seqno + * of loss_prev; and it must not equal that of any valid history entry. + */ +static void __do_track_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u64 n1) { - struct dccp_rx_hist_entry *entry, *next, *iter; - u8 num_later = 0; - - iter = dccp_rx_hist_head(rx_list); - if (iter == NULL) - dccp_rx_hist_add_entry(rx_list, packet); - else { - const u64 seqno = packet->dccphrx_seqno; - - if (after48(seqno, iter->dccphrx_seqno)) - dccp_rx_hist_add_entry(rx_list, packet); - else { - if (dccp_rx_hist_entry_data_packet(iter)) - num_later = 1; - - list_for_each_entry_continue(iter, rx_list, - dccphrx_node) { - if (after48(seqno, iter->dccphrx_seqno)) { - dccp_rx_hist_add_entry(&iter->dccphrx_node, - packet); - goto trim_history; - } - - if (dccp_rx_hist_entry_data_packet(iter)) - num_later++; - - if (num_later == TFRC_RECV_NUM_LATE_LOSS) { - dccp_rx_hist_entry_delete(hist, packet); - return 1; - } - } + u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, + s1 = DCCP_SKB_CB(skb)->dccpd_seq; - if (num_later < TFRC_RECV_NUM_LATE_LOSS) - dccp_rx_hist_add_entry(rx_list, packet); - /* - * FIXME: else what? should we destroy the packet - * like above? - */ - } + if (!dccp_loss_free(s0, s1, n1)) { /* gap between S0 and S1 */ + h->loss_count = 1; + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n1); } +} -trim_history: - /* - * Trim history (remove all packets after the NUM_LATE_LOSS + 1 - * data packets) - */ - num_later = TFRC_RECV_NUM_LATE_LOSS + 1; - - if (!list_empty(li_list)) { - list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) { - if (num_later == 0) { - list_del_init(&entry->dccphrx_node); - dccp_rx_hist_entry_delete(hist, entry); - } else if (dccp_rx_hist_entry_data_packet(entry)) - --num_later; - } - } else { - int step = 0; - u8 win_count = 0; /* Not needed, but lets shut up gcc */ - int tmp; +static void __one_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n2) +{ + u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, + s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, + s2 = DCCP_SKB_CB(skb)->dccpd_seq; + + if (likely(dccp_delta_seqno(s1, s2) > 0)) { /* S1 < S2 */ + h->loss_count = 2; + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n2); + return; + } + + /* S0 < S2 < S1 */ + + if (dccp_loss_free(s0, s2, n2)) { + u64 n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp; + + if (dccp_loss_free(s2, s1, n1)) { + /* hole is filled: S0, S2, and S1 are consecutive */ + h->loss_count = 0; + h->loss_start = tfrc_rx_hist_index(h, 1); + } else + /* gap between S2 and S1: just update loss_prev */ + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n2); + + } else { /* gap between S0 and S2 */ /* - * We have no loss interval history so we need at least one - * rtt:s of data packets to approximate rtt. + * Reorder history to insert S2 between S0 and S1 */ - list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) { - if (num_later == 0) { - switch (step) { - case 0: - step = 1; - /* OK, find next data packet */ - num_later = 1; - break; - case 1: - step = 2; - /* OK, find next data packet */ - num_later = 1; - win_count = entry->dccphrx_ccval; - break; - case 2: - tmp = win_count - entry->dccphrx_ccval; - if (tmp < 0) - tmp += TFRC_WIN_COUNT_LIMIT; - if (tmp > TFRC_WIN_COUNT_PER_RTT + 1) { - /* - * We have found a packet older - * than one rtt remove the rest - */ - step = 3; - } else /* OK, find next data packet */ - num_later = 1; - break; - case 3: - list_del_init(&entry->dccphrx_node); - dccp_rx_hist_entry_delete(hist, entry); - break; - } - } else if (dccp_rx_hist_entry_data_packet(entry)) - --num_later; - } + tfrc_rx_hist_swap(h, 0, 3); + h->loss_start = tfrc_rx_hist_index(h, 3); + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n2); + h->loss_count = 2; } - - return 0; } -EXPORT_SYMBOL_GPL(dccp_rx_hist_add_packet); - -u64 dccp_rx_hist_detect_loss(struct list_head *rx_list, - struct list_head *li_list, u8 *win_loss) +/* return 1 if a new loss event has been identified */ +static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3) { - struct dccp_rx_hist_entry *entry, *next, *packet; - struct dccp_rx_hist_entry *a_loss = NULL; - struct dccp_rx_hist_entry *b_loss = NULL; - u64 seq_loss = DCCP_MAX_SEQNO + 1; - u8 num_later = TFRC_RECV_NUM_LATE_LOSS; - - list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) { - if (num_later == 0) { - b_loss = entry; - break; - } else if (dccp_rx_hist_entry_data_packet(entry)) - --num_later; + u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, + s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, + s2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_seqno, + s3 = DCCP_SKB_CB(skb)->dccpd_seq; + + if (likely(dccp_delta_seqno(s2, s3) > 0)) { /* S2 < S3 */ + h->loss_count = 3; + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 3), skb, n3); + return 1; } - if (b_loss == NULL) - goto out; + /* S3 < S2 */ - num_later = 1; - list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) { - if (num_later == 0) { - a_loss = entry; - break; - } else if (dccp_rx_hist_entry_data_packet(entry)) - --num_later; + if (dccp_delta_seqno(s1, s3) > 0) { /* S1 < S3 < S2 */ + /* + * Reorder history to insert S3 between S1 and S2 + */ + tfrc_rx_hist_swap(h, 2, 3); + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n3); + h->loss_count = 3; + return 1; } - if (a_loss == NULL) { - if (list_empty(li_list)) { - /* no loss event have occured yet */ - LIMIT_NETDEBUG("%s: TODO: find a lost data packet by " - "comparing to initial seqno\n", - __FUNCTION__); - goto out; - } else { - LIMIT_NETDEBUG("%s: Less than 4 data pkts in history!", - __FUNCTION__); - goto out; - } - } + /* S0 < S3 < S1 */ - /* Locate a lost data packet */ - entry = packet = b_loss; - list_for_each_entry_safe_continue(entry, next, rx_list, dccphrx_node) { - u64 delta = dccp_delta_seqno(entry->dccphrx_seqno, - packet->dccphrx_seqno); - - if (delta != 0) { - if (dccp_rx_hist_entry_data_packet(packet)) - --delta; - /* - * FIXME: check this, probably this % usage is because - * in earlier drafts the ndp count was just 8 bits - * long, but now it cam be up to 24 bits long. - */ -#if 0 - if (delta % DCCP_NDP_LIMIT != - (packet->dccphrx_ndp - - entry->dccphrx_ndp) % DCCP_NDP_LIMIT) -#endif - if (delta != packet->dccphrx_ndp - entry->dccphrx_ndp) { - seq_loss = entry->dccphrx_seqno; - dccp_inc_seqno(&seq_loss); + if (dccp_loss_free(s0, s3, n3)) { + u64 n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp; + + if (dccp_loss_free(s3, s1, n1)) { + /* hole between S0 and S1 filled by S3 */ + u64 n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp; + + if (dccp_loss_free(s1, s2, n2)) { + /* entire hole filled by S0, S3, S1, S2 */ + h->loss_start = tfrc_rx_hist_index(h, 2); + h->loss_count = 0; + } else { + /* gap remains between S1 and S2 */ + h->loss_start = tfrc_rx_hist_index(h, 1); + h->loss_count = 1; } - } - packet = entry; - if (packet == a_loss) - break; + + } else /* gap exists between S3 and S1, loss_count stays at 2 */ + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n3); + + return 0; } -out: - if (seq_loss != DCCP_MAX_SEQNO + 1) - *win_loss = a_loss->dccphrx_ccval; - else - *win_loss = 0; /* Paranoia */ - return seq_loss; -} + /* + * The remaining case: S0 < S3 < S1 < S2; gap between S0 and S3 + * Reorder history to insert S3 between S0 and S1. + */ + tfrc_rx_hist_swap(h, 0, 3); + h->loss_start = tfrc_rx_hist_index(h, 3); + tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n3); + h->loss_count = 3; -EXPORT_SYMBOL_GPL(dccp_rx_hist_detect_loss); + return 1; +} -struct dccp_tx_hist *dccp_tx_hist_new(const char *name) +/* recycle RX history records to continue loss detection if necessary */ +static void __three_after_loss(struct tfrc_rx_hist *h) { - struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC); - static const char dccp_tx_hist_mask[] = "tx_hist_%s"; - char *slab_name; - - if (hist == NULL) - goto out; - - slab_name = kmalloc(strlen(name) + sizeof(dccp_tx_hist_mask) - 1, - GFP_ATOMIC); - if (slab_name == NULL) - goto out_free_hist; - - sprintf(slab_name, dccp_tx_hist_mask, name); - hist->dccptxh_slab = kmem_cache_create(slab_name, - sizeof(struct dccp_tx_hist_entry), - 0, SLAB_HWCACHE_ALIGN, - NULL, NULL); - if (hist->dccptxh_slab == NULL) - goto out_free_slab_name; -out: - return hist; -out_free_slab_name: - kfree(slab_name); -out_free_hist: - kfree(hist); - hist = NULL; - goto out; + /* + * At this stage we know already that there is a gap between S0 and S1 + * (since S0 was the highest sequence number received before detecting + * the loss). To recycle the loss record, it is thus only necessary to + * check for other possible gaps between S1/S2 and between S2/S3. + */ + u64 s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno, + s2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_seqno, + s3 = tfrc_rx_hist_entry(h, 3)->tfrchrx_seqno; + u64 n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp, + n3 = tfrc_rx_hist_entry(h, 3)->tfrchrx_ndp; + + if (dccp_loss_free(s1, s2, n2)) { + + if (dccp_loss_free(s2, s3, n3)) { + /* no gap between S2 and S3: entire hole is filled */ + h->loss_start = tfrc_rx_hist_index(h, 3); + h->loss_count = 0; + } else { + /* gap between S2 and S3 */ + h->loss_start = tfrc_rx_hist_index(h, 2); + h->loss_count = 1; + } + + } else { /* gap between S1 and S2 */ + h->loss_start = tfrc_rx_hist_index(h, 1); + h->loss_count = 2; + } } -EXPORT_SYMBOL_GPL(dccp_tx_hist_new); +/** + * tfrc_rx_handle_loss - Loss detection and further processing + * @h: The non-empty RX history object + * @lh: Loss Intervals database to update + * @skb: Currently received packet + * @ndp: The NDP count belonging to @skb + * @calc_first_li: Caller-dependent computation of first loss interval in @lh + * @sk: Used by @calc_first_li (see tfrc_lh_interval_add) + * + * Chooses action according to pending loss, updates LI database when a new + * loss was detected, and does required post-processing. Returns 1 when caller + * should send feedback, 0 otherwise. + * Since it also takes care of reordering during loss detection and updates the + * records accordingly, the caller should not perform any more RX history + * operations when loss_count is greater than 0 after calling this function. + */ +int tfrc_rx_handle_loss(struct tfrc_rx_hist *h, + struct tfrc_loss_hist *lh, + struct sk_buff *skb, const u64 ndp, + u32 (*calc_first_li)(struct sock *), struct sock *sk) +{ + int is_new_loss = 0; + + if (h->loss_count == 0) { + __do_track_loss(h, skb, ndp); + } else if (h->loss_count == 1) { + __one_after_loss(h, skb, ndp); + } else if (h->loss_count != 2) { + DCCP_BUG("invalid loss_count %d", h->loss_count); + } else if (__two_after_loss(h, skb, ndp)) { + /* + * Update Loss Interval database and recycle RX records + */ + is_new_loss = tfrc_lh_interval_add(lh, h, calc_first_li, sk); + __three_after_loss(h); + } + return is_new_loss; +} -void dccp_tx_hist_delete(struct dccp_tx_hist *hist) +int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h) { - const char* name = kmem_cache_name(hist->dccptxh_slab); + int i; - kmem_cache_destroy(hist->dccptxh_slab); - kfree(name); - kfree(hist); -} + for (i = 0; i <= TFRC_NDUPACK; i++) { + h->ring[i] = kmem_cache_alloc(tfrc_rx_hist_slab, GFP_ATOMIC); + if (h->ring[i] == NULL) + goto out_free; + } -EXPORT_SYMBOL_GPL(dccp_tx_hist_delete); + h->loss_count = h->loss_start = 0; + return 0; + +out_free: + while (i-- != 0) { + kmem_cache_free(tfrc_rx_hist_slab, h->ring[i]); + h->ring[i] = NULL; + } + return -ENOBUFS; +} -struct dccp_tx_hist_entry * - dccp_tx_hist_find_entry(const struct list_head *list, const u64 seq) +void tfrc_rx_hist_purge(struct tfrc_rx_hist *h) { - struct dccp_tx_hist_entry *packet = NULL, *entry; + int i; - list_for_each_entry(entry, list, dccphtx_node) - if (entry->dccphtx_seqno == seq) { - packet = entry; - break; + for (i = 0; i <= TFRC_NDUPACK; ++i) + if (h->ring[i] != NULL) { + kmem_cache_free(tfrc_rx_hist_slab, h->ring[i]); + h->ring[i] = NULL; } - - return packet; } -EXPORT_SYMBOL_GPL(dccp_tx_hist_find_entry); - -void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist, - struct list_head *list, - struct dccp_tx_hist_entry *packet) +/** + * tfrc_rx_hist_rtt_last_s - reference entry to compute RTT samples against + */ +static inline struct tfrc_rx_hist_entry * + tfrc_rx_hist_rtt_last_s(const struct tfrc_rx_hist *h) { - struct dccp_tx_hist_entry *next; - - list_for_each_entry_safe_continue(packet, next, list, dccphtx_node) { - list_del_init(&packet->dccphtx_node); - dccp_tx_hist_entry_delete(hist, packet); - } + return h->ring[0]; } -EXPORT_SYMBOL_GPL(dccp_tx_hist_purge_older); +/** + * tfrc_rx_hist_rtt_prev_s - previously suitable (wrt rtt_last_s) RTT-sampling entry + */ +static inline struct tfrc_rx_hist_entry * + tfrc_rx_hist_rtt_prev_s(const struct tfrc_rx_hist *h) +{ + return h->ring[h->rtt_sample_prev]; +} -void dccp_tx_hist_purge(struct dccp_tx_hist *hist, struct list_head *list) +/** + * tfrc_rx_hist_sample_rtt - Sample RTT from timestamp / CCVal + * Based on ideas presented in RFC 4342, 8.1. Returns 0 if it was not able + * to compute a sample with given data - calling function should check this. + */ +u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, const struct sk_buff *skb) { - struct dccp_tx_hist_entry *entry, *next; + u32 sample = 0, + delta_v = SUB16(dccp_hdr(skb)->dccph_ccval, + tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval); + + if (delta_v < 1 || delta_v > 4) { /* unsuitable CCVal delta */ + if (h->rtt_sample_prev == 2) { /* previous candidate stored */ + sample = SUB16(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval, + tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval); + if (sample) + sample = 4 / sample * + ktime_us_delta(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_tstamp, + tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp); + else /* + * FIXME: This condition is in principle not + * possible but occurs when CCID is used for + * two-way data traffic. I have tried to trace + * it, but the cause does not seem to be here. + */ + DCCP_BUG("please report to dccp@vger.kernel.org" + " => prev = %u, last = %u", + tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval, + tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval); + } else if (delta_v < 1) { + h->rtt_sample_prev = 1; + goto keep_ref_for_next_time; + } - list_for_each_entry_safe(entry, next, list, dccphtx_node) { - list_del_init(&entry->dccphtx_node); - dccp_tx_hist_entry_delete(hist, entry); + } else if (delta_v == 4) /* optimal match */ + sample = ktime_to_us(net_timedelta(tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp)); + else { /* suboptimal match */ + h->rtt_sample_prev = 2; + goto keep_ref_for_next_time; } -} -EXPORT_SYMBOL_GPL(dccp_tx_hist_purge); + if (unlikely(sample > DCCP_SANE_RTT_MAX)) { + DCCP_WARN("RTT sample %u too large, using max\n", sample); + sample = DCCP_SANE_RTT_MAX; + } + + h->rtt_sample_prev = 0; /* use current entry as next reference */ +keep_ref_for_next_time: -MODULE_AUTHOR("Ian McDonald <iam4@cs.waikato.ac.nz>, " - "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>"); -MODULE_DESCRIPTION("DCCP TFRC library"); -MODULE_LICENSE("GPL"); + return sample; +} diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h index 122e96737ff..ee362b0b630 100644 --- a/net/dccp/ccids/lib/packet_history.h +++ b/net/dccp/ccids/lib/packet_history.h @@ -1,13 +1,12 @@ /* - * net/dccp/packet_history.h + * Packet RX/TX history data structures and routines for TFRC-based protocols. * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * - * An implementation of the DCCP protocol + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand. * * This code has been developed by the University of Waikato WAND * research group. For further information please see http://www.wand.net.nz/ - * or e-mail Ian McDonald - iam4@cs.waikato.ac.nz + * or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz * * This code also uses code from Lulea University, rereleased as GPL by its * authors: @@ -37,164 +36,120 @@ #ifndef _DCCP_PKT_HIST_ #define _DCCP_PKT_HIST_ -#include <linux/config.h> #include <linux/list.h> #include <linux/slab.h> -#include <linux/time.h> - -#include "../../dccp.h" - -/* Number of later packets received before one is considered lost */ -#define TFRC_RECV_NUM_LATE_LOSS 3 - -#define TFRC_WIN_COUNT_PER_RTT 4 -#define TFRC_WIN_COUNT_LIMIT 16 - -struct dccp_tx_hist_entry { - struct list_head dccphtx_node; - u64 dccphtx_seqno:48, - dccphtx_ccval:4, - dccphtx_sent:1; - u32 dccphtx_rtt; - struct timeval dccphtx_tstamp; -}; - -struct dccp_rx_hist_entry { - struct list_head dccphrx_node; - u64 dccphrx_seqno:48, - dccphrx_ccval:4, - dccphrx_type:4; - u32 dccphrx_ndp; /* In fact it is from 8 to 24 bits */ - struct timeval dccphrx_tstamp; -}; - -struct dccp_tx_hist { - kmem_cache_t *dccptxh_slab; -}; +#include "tfrc.h" -extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name); -extern void dccp_tx_hist_delete(struct dccp_tx_hist *hist); - -struct dccp_rx_hist { - kmem_cache_t *dccprxh_slab; +/** + * tfrc_tx_hist_entry - Simple singly-linked TX history list + * @next: next oldest entry (LIFO order) + * @seqno: sequence number of this entry + * @stamp: send time of packet with sequence number @seqno + */ +struct tfrc_tx_hist_entry { + struct tfrc_tx_hist_entry *next; + u64 seqno; + ktime_t stamp; }; -extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name); -extern void dccp_rx_hist_delete(struct dccp_rx_hist *hist); -extern struct dccp_rx_hist_entry * - dccp_rx_hist_find_data_packet(const struct list_head *list); - -static inline struct dccp_tx_hist_entry * - dccp_tx_hist_entry_new(struct dccp_tx_hist *hist, - const gfp_t prio) +static inline struct tfrc_tx_hist_entry * + tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 seqno) { - struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab, - prio); - - if (entry != NULL) - entry->dccphtx_sent = 0; - - return entry; + while (head != NULL && head->seqno != seqno) + head = head->next; + return head; } -static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist, - struct dccp_tx_hist_entry *entry) -{ - if (entry != NULL) - kmem_cache_free(hist->dccptxh_slab, entry); -} +int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno); +void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp); -extern struct dccp_tx_hist_entry * - dccp_tx_hist_find_entry(const struct list_head *list, - const u64 seq); +/* Subtraction a-b modulo-16, respects circular wrap-around */ +#define SUB16(a, b) (((a) + 16 - (b)) & 0xF) -static inline void dccp_tx_hist_add_entry(struct list_head *list, - struct dccp_tx_hist_entry *entry) -{ - list_add(&entry->dccphtx_node, list); -} +/* Number of packets to wait after a missing packet (RFC 4342, 6.1) */ +#define TFRC_NDUPACK 3 -extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist, - struct list_head *list, - struct dccp_tx_hist_entry *next); +/** + * tfrc_rx_hist_entry - Store information about a single received packet + * @tfrchrx_seqno: DCCP packet sequence number + * @tfrchrx_ccval: window counter value of packet (RFC 4342, 8.1) + * @tfrchrx_ndp: the NDP count (if any) of the packet + * @tfrchrx_tstamp: actual receive time of packet + */ +struct tfrc_rx_hist_entry { + u64 tfrchrx_seqno:48, + tfrchrx_ccval:4, + tfrchrx_type:4; + u64 tfrchrx_ndp:48; + ktime_t tfrchrx_tstamp; +}; -extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist, - struct list_head *list); +/** + * tfrc_rx_hist - RX history structure for TFRC-based protocols + * @ring: Packet history for RTT sampling and loss detection + * @loss_count: Number of entries in circular history + * @loss_start: Movable index (for loss detection) + * @rtt_sample_prev: Used during RTT sampling, points to candidate entry + */ +struct tfrc_rx_hist { + struct tfrc_rx_hist_entry *ring[TFRC_NDUPACK + 1]; + u8 loss_count:2, + loss_start:2; +#define rtt_sample_prev loss_start +}; -static inline struct dccp_tx_hist_entry * - dccp_tx_hist_head(struct list_head *list) +/** + * tfrc_rx_hist_index - index to reach n-th entry after loss_start + */ +static inline u8 tfrc_rx_hist_index(const struct tfrc_rx_hist *h, const u8 n) { - struct dccp_tx_hist_entry *head = NULL; - - if (!list_empty(list)) - head = list_entry(list->next, struct dccp_tx_hist_entry, - dccphtx_node); - return head; + return (h->loss_start + n) & TFRC_NDUPACK; } -static inline struct dccp_rx_hist_entry * - dccp_rx_hist_entry_new(struct dccp_rx_hist *hist, - const struct sock *sk, - const u32 ndp, - const struct sk_buff *skb, - const gfp_t prio) +/** + * tfrc_rx_hist_last_rcv - entry with highest-received-seqno so far + */ +static inline struct tfrc_rx_hist_entry * + tfrc_rx_hist_last_rcv(const struct tfrc_rx_hist *h) { - struct dccp_rx_hist_entry *entry = kmem_cache_alloc(hist->dccprxh_slab, - prio); - - if (entry != NULL) { - const struct dccp_hdr *dh = dccp_hdr(skb); - - entry->dccphrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq; - entry->dccphrx_ccval = dh->dccph_ccval; - entry->dccphrx_type = dh->dccph_type; - entry->dccphrx_ndp = ndp; - dccp_timestamp(sk, &entry->dccphrx_tstamp); - } - - return entry; + return h->ring[tfrc_rx_hist_index(h, h->loss_count)]; } -static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist, - struct dccp_rx_hist_entry *entry) +/** + * tfrc_rx_hist_entry - return the n-th history entry after loss_start + */ +static inline struct tfrc_rx_hist_entry * + tfrc_rx_hist_entry(const struct tfrc_rx_hist *h, const u8 n) { - if (entry != NULL) - kmem_cache_free(hist->dccprxh_slab, entry); + return h->ring[tfrc_rx_hist_index(h, n)]; } -extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist, - struct list_head *list); - -static inline void dccp_rx_hist_add_entry(struct list_head *list, - struct dccp_rx_hist_entry *entry) +/** + * tfrc_rx_hist_loss_prev - entry with highest-received-seqno before loss was detected + */ +static inline struct tfrc_rx_hist_entry * + tfrc_rx_hist_loss_prev(const struct tfrc_rx_hist *h) { - list_add(&entry->dccphrx_node, list); + return h->ring[h->loss_start]; } -static inline struct dccp_rx_hist_entry * - dccp_rx_hist_head(struct list_head *list) +/* indicate whether previously a packet was detected missing */ +static inline bool tfrc_rx_hist_loss_pending(const struct tfrc_rx_hist *h) { - struct dccp_rx_hist_entry *head = NULL; - - if (!list_empty(list)) - head = list_entry(list->next, struct dccp_rx_hist_entry, - dccphrx_node); - return head; + return h->loss_count > 0; } -static inline int - dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry) -{ - return entry->dccphrx_type == DCCP_PKT_DATA || - entry->dccphrx_type == DCCP_PKT_DATAACK; -} +void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h, const struct sk_buff *skb, + const u64 ndp); -extern int dccp_rx_hist_add_packet(struct dccp_rx_hist *hist, - struct list_head *rx_list, - struct list_head *li_list, - struct dccp_rx_hist_entry *packet); +int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb); -extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list, - struct list_head *li_list, u8 *win_loss); +struct tfrc_loss_hist; +int tfrc_rx_handle_loss(struct tfrc_rx_hist *h, struct tfrc_loss_hist *lh, + struct sk_buff *skb, const u64 ndp, + u32 (*first_li)(struct sock *sk), struct sock *sk); +u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, const struct sk_buff *skb); +int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h); +void tfrc_rx_hist_purge(struct tfrc_rx_hist *h); #endif /* _DCCP_PKT_HIST_ */ diff --git a/net/dccp/ccids/lib/tfrc.c b/net/dccp/ccids/lib/tfrc.c new file mode 100644 index 00000000000..62b5828acde --- /dev/null +++ b/net/dccp/ccids/lib/tfrc.c @@ -0,0 +1,45 @@ +/* + * TFRC library initialisation + * + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> + */ +#include <linux/moduleparam.h> +#include "tfrc.h" + +#ifdef CONFIG_IP_DCCP_TFRC_DEBUG +bool tfrc_debug; +module_param(tfrc_debug, bool, 0644); +MODULE_PARM_DESC(tfrc_debug, "Enable TFRC debug messages"); +#endif + +int __init tfrc_lib_init(void) +{ + int rc = tfrc_li_init(); + + if (rc) + goto out; + + rc = tfrc_tx_packet_history_init(); + if (rc) + goto out_free_loss_intervals; + + rc = tfrc_rx_packet_history_init(); + if (rc) + goto out_free_tx_history; + return 0; + +out_free_tx_history: + tfrc_tx_packet_history_exit(); +out_free_loss_intervals: + tfrc_li_exit(); +out: + return rc; +} + +void tfrc_lib_exit(void) +{ + tfrc_rx_packet_history_exit(); + tfrc_tx_packet_history_exit(); + tfrc_li_exit(); +} diff --git a/net/dccp/ccids/lib/tfrc.h b/net/dccp/ccids/lib/tfrc.h index 130c4c40cfe..40ee7d62b65 100644 --- a/net/dccp/ccids/lib/tfrc.h +++ b/net/dccp/ccids/lib/tfrc.h @@ -1,22 +1,77 @@ #ifndef _TFRC_H_ #define _TFRC_H_ /* - * net/dccp/ccids/lib/tfrc.h - * - * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> - * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> - * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon + * Copyright (c) 2007 The University of Aberdeen, Scotland, UK + * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand. + * Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz> + * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ - #include <linux/types.h> +#include <linux/math64.h> +#include "../../dccp.h" + +/* internal includes that this library exports: */ +#include "loss_interval.h" +#include "packet_history.h" + +#ifdef CONFIG_IP_DCCP_TFRC_DEBUG +extern bool tfrc_debug; +#define tfrc_pr_debug(format, a...) DCCP_PR_DEBUG(tfrc_debug, format, ##a) +#else +#define tfrc_pr_debug(format, a...) +#endif + +/* integer-arithmetic divisions of type (a * 1000000)/b */ +static inline u64 scaled_div(u64 a, u64 b) +{ + BUG_ON(b == 0); + return div64_u64(a * 1000000, b); +} + +static inline u32 scaled_div32(u64 a, u64 b) +{ + u64 result = scaled_div(a, b); + + if (result > UINT_MAX) { + DCCP_CRIT("Overflow: %llu/%llu > UINT_MAX", + (unsigned long long)a, (unsigned long long)b); + return UINT_MAX; + } + return result; +} + +/** + * tfrc_ewma - Exponentially weighted moving average + * @weight: Weight to be used as damping factor, in units of 1/10 + */ +static inline u32 tfrc_ewma(const u32 avg, const u32 newval, const u8 weight) +{ + return avg ? (weight * avg + (10 - weight) * newval) / 10 : newval; +} + +u32 tfrc_calc_x(u16 s, u32 R, u32 p); +u32 tfrc_calc_x_reverse_lookup(u32 fvalue); +u32 tfrc_invert_loss_event_rate(u32 loss_event_rate); + +int tfrc_tx_packet_history_init(void); +void tfrc_tx_packet_history_exit(void); +int tfrc_rx_packet_history_init(void); +void tfrc_rx_packet_history_exit(void); -extern u32 tfrc_calc_x(u16 s, u32 R, u32 p); -extern u32 tfrc_calc_x_reverse_lookup(u32 fvalue); +int tfrc_li_init(void); +void tfrc_li_exit(void); +#ifdef CONFIG_IP_DCCP_TFRC_LIB +int tfrc_lib_init(void); +void tfrc_lib_exit(void); +#else +#define tfrc_lib_init() (0) +#define tfrc_lib_exit() +#endif #endif /* _TFRC_H_ */ diff --git a/net/dccp/ccids/lib/tfrc_equation.c b/net/dccp/ccids/lib/tfrc_equation.c index d2b5933b451..88ef98285be 100644 --- a/net/dccp/ccids/lib/tfrc_equation.c +++ b/net/dccp/ccids/lib/tfrc_equation.c @@ -1,8 +1,6 @@ /* - * net/dccp/ccids/lib/tfrc_equation.c - * * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand. - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz> * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon * @@ -12,19 +10,84 @@ * (at your option) any later version. */ -#include <linux/config.h> #include <linux/module.h> - -#include <asm/bug.h> -#include <asm/div64.h> - +#include "../../dccp.h" #include "tfrc.h" #define TFRC_CALC_X_ARRSIZE 500 +#define TFRC_CALC_X_SPLIT 50000 /* 0.05 * 1000000, details below */ +#define TFRC_SMALLEST_P (TFRC_CALC_X_SPLIT/TFRC_CALC_X_ARRSIZE) -#define TFRC_CALC_X_SPLIT 50000 -/* equivalent to 0.05 */ - +/* + TFRC TCP Reno Throughput Equation Lookup Table for f(p) + + The following two-column lookup table implements a part of the TCP throughput + equation from [RFC 3448, sec. 3.1]: + + s + X_calc = -------------------------------------------------------------- + R * sqrt(2*b*p/3) + (3 * t_RTO * sqrt(3*b*p/8) * (p + 32*p^3)) + + Where: + X is the transmit rate in bytes/second + s is the packet size in bytes + R is the round trip time in seconds + p is the loss event rate, between 0 and 1.0, of the number of loss + events as a fraction of the number of packets transmitted + t_RTO is the TCP retransmission timeout value in seconds + b is the number of packets acknowledged by a single TCP ACK + + We can assume that b = 1 and t_RTO is 4 * R. The equation now becomes: + + s + X_calc = ------------------------------------------------------- + R * sqrt(p*2/3) + (12 * R * sqrt(p*3/8) * (p + 32*p^3)) + + which we can break down into: + + s + X_calc = --------- + R * f(p) + + where f(p) is given for 0 < p <= 1 by: + + f(p) = sqrt(2*p/3) + 12 * sqrt(3*p/8) * (p + 32*p^3) + + Since this is kernel code, floating-point arithmetic is avoided in favour of + integer arithmetic. This means that nearly all fractional parameters are + scaled by 1000000: + * the parameters p and R + * the return result f(p) + The lookup table therefore actually tabulates the following function g(q): + + g(q) = 1000000 * f(q/1000000) + + Hence, when p <= 1, q must be less than or equal to 1000000. To achieve finer + granularity for the practically more relevant case of small values of p (up to + 5%), the second column is used; the first one ranges up to 100%. This split + corresponds to the value of q = TFRC_CALC_X_SPLIT. At the same time this also + determines the smallest resolution possible with this lookup table: + + TFRC_SMALLEST_P = TFRC_CALC_X_SPLIT / TFRC_CALC_X_ARRSIZE + + The entire table is generated by: + for(i=0; i < TFRC_CALC_X_ARRSIZE; i++) { + lookup[i][0] = g((i+1) * 1000000/TFRC_CALC_X_ARRSIZE); + lookup[i][1] = g((i+1) * TFRC_CALC_X_SPLIT/TFRC_CALC_X_ARRSIZE); + } + + With the given configuration, we have, with M = TFRC_CALC_X_ARRSIZE-1, + lookup[0][0] = g(1000000/(M+1)) = 1000000 * f(0.2%) + lookup[M][0] = g(1000000) = 1000000 * f(100%) + lookup[0][1] = g(TFRC_SMALLEST_P) = 1000000 * f(0.01%) + lookup[M][1] = g(TFRC_CALC_X_SPLIT) = 1000000 * f(5%) + + In summary, the two columns represent f(p) for the following ranges: + * The first column is for 0.002 <= p <= 1.0 + * The second column is for 0.0001 <= p <= 0.05 + Where the columns overlap, the second (finer-grained) is given preference, + i.e. the first column is used only for p >= 0.05. + */ static const u32 tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE][2] = { { 37172, 8172 }, { 53499, 11567 }, @@ -528,117 +591,115 @@ static const u32 tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE][2] = { { 243315981, 271305 } }; -/* Calculate the send rate as per section 3.1 of RFC3448 - -Returns send rate in bytes per second - -Integer maths and lookups are used as not allowed floating point in kernel - -The function for Xcalc as per section 3.1 of RFC3448 is: - -X = s - ------------------------------------------------------------- - R*sqrt(2*b*p/3) + (t_RTO * (3*sqrt(3*b*p/8) * p * (1+32*p^2))) - -where -X is the trasmit rate in bytes/second -s is the packet size in bytes -R is the round trip time in seconds -p is the loss event rate, between 0 and 1.0, of the number of loss events - as a fraction of the number of packets transmitted -t_RTO is the TCP retransmission timeout value in seconds -b is the number of packets acknowledged by a single TCP acknowledgement - -we can assume that b = 1 and t_RTO is 4 * R. With this the equation becomes: - -X = s - ----------------------------------------------------------------------- - R * sqrt(2 * p / 3) + (12 * R * (sqrt(3 * p / 8) * p * (1 + 32 * p^2))) - - -which we can break down into: - -X = s - -------- - R * f(p) - -where f(p) = sqrt(2 * p / 3) + (12 * sqrt(3 * p / 8) * p * (1 + 32 * p * p)) - -Function parameters: -s - bytes -R - RTT in usecs -p - loss rate (decimal fraction multiplied by 1,000,000) - -Returns Xcalc in bytes per second - -DON'T alter this code unless you run test cases against it as the code -has been manipulated to stop underflow/overlow. +/* return largest index i such that fval <= lookup[i][small] */ +static inline u32 tfrc_binsearch(u32 fval, u8 small) +{ + u32 try, low = 0, high = TFRC_CALC_X_ARRSIZE - 1; + + while (low < high) { + try = (low + high) / 2; + if (fval <= tfrc_calc_x_lookup[try][small]) + high = try; + else + low = try + 1; + } + return high; +} -*/ +/** + * tfrc_calc_x - Calculate the send rate as per section 3.1 of RFC3448 + * @s: packet size in bytes + * @R: RTT scaled by 1000000 (i.e., microseconds) + * @p: loss ratio estimate scaled by 1000000 + * + * Returns X_calc in bytes per second (not scaled). + */ u32 tfrc_calc_x(u16 s, u32 R, u32 p) { - int index; + u16 index; u32 f; - u64 tmp1, tmp2; + u64 result; + + /* check against invalid parameters and divide-by-zero */ + BUG_ON(p > 1000000); /* p must not exceed 100% */ + BUG_ON(p == 0); /* f(0) = 0, divide by zero */ + if (R == 0) { /* possible divide by zero */ + DCCP_CRIT("WARNING: RTT is 0, returning maximum X_calc."); + return ~0U; + } + + if (p <= TFRC_CALC_X_SPLIT) { /* 0.0000 < p <= 0.05 */ + if (p < TFRC_SMALLEST_P) { /* 0.0000 < p < 0.0001 */ + DCCP_WARN("Value of p (%d) below resolution. " + "Substituting %d\n", p, TFRC_SMALLEST_P); + index = 0; + } else /* 0.0001 <= p <= 0.05 */ + index = p/TFRC_SMALLEST_P - 1; - if (p < TFRC_CALC_X_SPLIT) - index = (p / (TFRC_CALC_X_SPLIT / TFRC_CALC_X_ARRSIZE)) - 1; - else - index = (p / (1000000 / TFRC_CALC_X_ARRSIZE)) - 1; - - if (index < 0) - /* p should be 0 unless there is a bug in my code */ - index = 0; - - if (R == 0) - R = 1; /* RTT can't be zero or else divide by zero */ - - BUG_ON(index >= TFRC_CALC_X_ARRSIZE); - - if (p >= TFRC_CALC_X_SPLIT) - f = tfrc_calc_x_lookup[index][0]; - else f = tfrc_calc_x_lookup[index][1]; - tmp1 = ((u64)s * 100000000); - tmp2 = ((u64)R * (u64)f); - do_div(tmp2, 10000); - do_div(tmp1, tmp2); - /* Don't alter above math unless you test due to overflow on 32 bit */ + } else { /* 0.05 < p <= 1.00 */ + index = p/(1000000/TFRC_CALC_X_ARRSIZE) - 1; - return (u32)tmp1; + f = tfrc_calc_x_lookup[index][0]; + } + + /* + * Compute X = s/(R*f(p)) in bytes per second. + * Since f(p) and R are both scaled by 1000000, we need to multiply by + * 1000000^2. To avoid overflow, the result is computed in two stages. + * This works under almost all reasonable operational conditions, for a + * wide range of parameters. Yet, should some strange combination of + * parameters result in overflow, the use of scaled_div32 will catch + * this and return UINT_MAX - which is a logically adequate consequence. + */ + result = scaled_div(s, R); + return scaled_div32(result, f); } -EXPORT_SYMBOL_GPL(tfrc_calc_x); - -/* - * args: fvalue - function value to match - * returns: p closest to that value +/** + * tfrc_calc_x_reverse_lookup - try to find p given f(p) + * @fvalue: function value to match, scaled by 1000000 * - * both fvalue and p are multiplied by 1,000,000 to use ints + * Returns closest match for p, also scaled by 1000000 */ u32 tfrc_calc_x_reverse_lookup(u32 fvalue) { - int ctr = 0; - int small; + int index; - if (fvalue < tfrc_calc_x_lookup[0][1]) + if (fvalue == 0) /* f(p) = 0 whenever p = 0 */ return 0; - if (fvalue <= tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE - 1][1]) - small = 1; - else if (fvalue > tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE - 1][0]) + /* Error cases. */ + if (fvalue < tfrc_calc_x_lookup[0][1]) { + DCCP_WARN("fvalue %u smaller than resolution\n", fvalue); + return TFRC_SMALLEST_P; + } + if (fvalue > tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE - 1][0]) { + DCCP_WARN("fvalue %u exceeds bounds!\n", fvalue); return 1000000; - else - small = 0; + } - while (fvalue > tfrc_calc_x_lookup[ctr][small]) - ctr++; + if (fvalue <= tfrc_calc_x_lookup[TFRC_CALC_X_ARRSIZE - 1][1]) { + index = tfrc_binsearch(fvalue, 1); + return (index + 1) * TFRC_CALC_X_SPLIT / TFRC_CALC_X_ARRSIZE; + } - if (small) - return TFRC_CALC_X_SPLIT * ctr / TFRC_CALC_X_ARRSIZE; - else - return 1000000 * ctr / TFRC_CALC_X_ARRSIZE; + /* else ... it must be in the coarse-grained column */ + index = tfrc_binsearch(fvalue, 0); + return (index + 1) * 1000000 / TFRC_CALC_X_ARRSIZE; } -EXPORT_SYMBOL_GPL(tfrc_calc_x_reverse_lookup); +/** + * tfrc_invert_loss_event_rate - Compute p so that 10^6 corresponds to 100% + * When @loss_event_rate is large, there is a chance that p is truncated to 0. + * To avoid re-entering slow-start in that case, we set p = TFRC_SMALLEST_P > 0. + */ +u32 tfrc_invert_loss_event_rate(u32 loss_event_rate) +{ + if (loss_event_rate == UINT_MAX) /* see RFC 4342, 8.5 */ + return 0; + if (unlikely(loss_event_rate == 0)) /* map 1/0 into 100% */ + return 1000000; + return max_t(u32, scaled_div(1, loss_event_rate), TFRC_SMALLEST_P); +} diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 93f26dd6e6c..c67816647cc 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -5,73 +5,138 @@ * * An implementation of the DCCP protocol * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ -#include <linux/config.h> #include <linux/dccp.h> +#include <linux/ktime.h> #include <net/snmp.h> #include <net/sock.h> #include <net/tcp.h> #include "ackvec.h" +/* + * DCCP - specific warning and debugging macros. + */ +#define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt, \ + __func__, ##a) +#define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \ + __FILE__, __LINE__, __func__) +#define DCCP_BUG(a...) do { DCCP_CRIT("BUG: " a); dump_stack(); } while(0) +#define DCCP_BUG_ON(cond) do { if (unlikely((cond) != 0)) \ + DCCP_BUG("\"%s\" holds (exception!)", \ + __stringify(cond)); \ + } while (0) + +#define DCCP_PRINTK(enable, fmt, args...) do { if (enable) \ + printk(fmt, ##args); \ + } while(0) +#define DCCP_PR_DEBUG(enable, fmt, a...) DCCP_PRINTK(enable, KERN_DEBUG \ + "%s: " fmt, __func__, ##a) + #ifdef CONFIG_IP_DCCP_DEBUG -extern int dccp_debug; - -#define dccp_pr_debug(format, a...) \ - do { if (dccp_debug) \ - printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \ - } while (0) -#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \ - printk(format, ##a); } while (0) +extern bool dccp_debug; +#define dccp_pr_debug(format, a...) DCCP_PR_DEBUG(dccp_debug, format, ##a) +#define dccp_pr_debug_cat(format, a...) DCCP_PRINTK(dccp_debug, format, ##a) +#define dccp_debug(fmt, a...) dccp_pr_debug_cat(KERN_DEBUG fmt, ##a) #else #define dccp_pr_debug(format, a...) #define dccp_pr_debug_cat(format, a...) +#define dccp_debug(format, a...) #endif extern struct inet_hashinfo dccp_hashinfo; -extern atomic_t dccp_orphan_count; -extern int dccp_tw_count; -extern void dccp_tw_deschedule(struct inet_timewait_sock *tw); - -extern void dccp_time_wait(struct sock *sk, int state, int timeo); +extern struct percpu_counter dccp_orphan_count; -/* FIXME: Right size this */ -#define DCCP_MAX_OPT_LEN 128 +void dccp_time_wait(struct sock *sk, int state, int timeo); -#define DCCP_MAX_PACKET_HDR 32 +/* + * Set safe upper bounds for header and option length. Since Data Offset is 8 + * bits (RFC 4340, sec. 5.1), the total header length can never be more than + * 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1): + * - DCCP-Response with ACK Subheader and 4 bytes of Service code OR + * - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields + * Hence a safe upper bound for the maximum option length is 1020-28 = 992 + */ +#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(uint32_t)) +#define DCCP_MAX_PACKET_HDR 28 +#define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR) +#define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER) -#define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER) +/* Upper bound for initial feature-negotiation overhead (padded to 32 bits) */ +#define DCCP_FEATNEG_OVERHEAD (32 * sizeof(uint32_t)) #define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT * state, about 60 seconds */ -/* draft-ietf-dccp-spec-11.txt initial RTO value */ -#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ)) +/* RFC 1122, 4.2.3.1 initial RTO value */ +#define DCCP_TIMEOUT_INIT ((unsigned int)(3 * HZ)) + +/* + * The maximum back-off value for retransmissions. This is needed for + * - retransmitting client-Requests (sec. 8.1.1), + * - retransmitting Close/CloseReq when closing (sec. 8.3), + * - feature-negotiation retransmission (sec. 6.6.3), + * - Acks in client-PARTOPEN state (sec. 8.1.5). + */ +#define DCCP_RTO_MAX ((unsigned int)(64 * HZ)) + +/* + * RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4 + */ +#define DCCP_SANE_RTT_MIN 100 +#define DCCP_FALLBACK_RTT (USEC_PER_SEC / 5) +#define DCCP_SANE_RTT_MAX (3 * USEC_PER_SEC) + +/* sysctl variables for DCCP */ +extern int sysctl_dccp_request_retries; +extern int sysctl_dccp_retries1; +extern int sysctl_dccp_retries2; +extern int sysctl_dccp_tx_qlen; +extern int sysctl_dccp_sync_ratelimit; -/* Maximal interval between probes for local resources. */ -#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U)) +/* + * 48-bit sequence number arithmetic (signed and unsigned) + */ +#define INT48_MIN 0x800000000000LL /* 2^47 */ +#define UINT48_MAX 0xFFFFFFFFFFFFLL /* 2^48 - 1 */ +#define COMPLEMENT48(x) (0x1000000000000LL - (x)) /* 2^48 - x */ +#define TO_SIGNED48(x) (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x))) +#define TO_UNSIGNED48(x) (((x) >= 0)? (x) : COMPLEMENT48(-(x))) +#define ADD48(a, b) (((a) + (b)) & UINT48_MAX) +#define SUB48(a, b) ADD48((a), COMPLEMENT48(b)) -#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */ +static inline void dccp_set_seqno(u64 *seqno, u64 value) +{ + *seqno = value & UINT48_MAX; +} -extern struct proto dccp_prot; +static inline void dccp_inc_seqno(u64 *seqno) +{ + *seqno = ADD48(*seqno, 1); +} + +/* signed mod-2^48 distance: pos. if seqno1 < seqno2, neg. if seqno1 > seqno2 */ +static inline s64 dccp_delta_seqno(const u64 seqno1, const u64 seqno2) +{ + u64 delta = SUB48(seqno2, seqno1); + + return TO_SIGNED48(delta); +} /* is seq1 < seq2 ? */ static inline int before48(const u64 seq1, const u64 seq2) { - return (s64)((seq1 << 16) - (seq2 << 16)) < 0; + return (s64)((seq2 << 16) - (seq1 << 16)) > 0; } /* is seq1 > seq2 ? */ -static inline int after48(const u64 seq1, const u64 seq2) -{ - return (s64)((seq2 << 16) - (seq1 << 16)) < 0; -} +#define after48(seq1, seq2) before48(seq2, seq1) /* is seq2 <= seq1 <= seq3 ? */ static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3) @@ -84,12 +149,36 @@ static inline u64 max48(const u64 seq1, const u64 seq2) return after48(seq1, seq2) ? seq1 : seq2; } +/** + * dccp_loss_count - Approximate the number of lost data packets in a burst loss + * @s1: last known sequence number before the loss ('hole') + * @s2: first sequence number seen after the 'hole' + * @ndp: NDP count on packet with sequence number @s2 + */ +static inline u64 dccp_loss_count(const u64 s1, const u64 s2, const u64 ndp) +{ + s64 delta = dccp_delta_seqno(s1, s2); + + WARN_ON(delta < 0); + delta -= ndp + 1; + + return delta > 0 ? delta : 0; +} + +/** + * dccp_loss_free - Evaluate condition for data loss from RFC 4340, 7.7.1 + */ +static inline bool dccp_loss_free(const u64 s1, const u64 s2, const u64 ndp) +{ + return dccp_loss_count(s1, s2, ndp) == 0; +} + enum { DCCP_MIB_NUM = 0, DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */ DCCP_MIB_ESTABRESETS, /* EstabResets */ DCCP_MIB_CURRESTAB, /* CurrEstab */ - DCCP_MIB_OUTSEGS, /* OutSegs */ + DCCP_MIB_OUTSEGS, /* OutSegs */ DCCP_MIB_OUTRSTS, DCCP_MIB_ABORTONTIMEOUT, DCCP_MIB_TIMEOUTS, @@ -106,171 +195,140 @@ enum { #define DCCP_MIB_MAX __DCCP_MIB_MAX struct dccp_mib { unsigned long mibs[DCCP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); #define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) #define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field) -#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field) #define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field) -#define DCCP_ADD_STATS_BH(field, val) \ - SNMP_ADD_STATS_BH(dccp_statistics, field, val) -#define DCCP_ADD_STATS_USER(field, val) \ - SNMP_ADD_STATS_USER(dccp_statistics, field, val) -extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb); +/* + * Checksumming routines + */ +static inline unsigned int dccp_csum_coverage(const struct sk_buff *skb) +{ + const struct dccp_hdr* dh = dccp_hdr(skb); + + if (dh->dccph_cscov == 0) + return skb->len; + return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32); +} -extern int dccp_send_response(struct sock *sk); -extern void dccp_send_ack(struct sock *sk); -extern void dccp_send_delayed_ack(struct sock *sk); -extern void dccp_send_sync(struct sock *sk, const u64 seq, - const enum dccp_pkt_type pkt_type); +static inline void dccp_csum_outgoing(struct sk_buff *skb) +{ + unsigned int cov = dccp_csum_coverage(skb); + + if (cov >= skb->len) + dccp_hdr(skb)->dccph_cscov = 0; -extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo); -extern void dccp_write_space(struct sock *sk); + skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0); +} -extern void dccp_init_xmit_timers(struct sock *sk); +void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb); + +int dccp_retransmit_skb(struct sock *sk); + +void dccp_send_ack(struct sock *sk); +void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, + struct request_sock *rsk); + +void dccp_send_sync(struct sock *sk, const u64 seq, + const enum dccp_pkt_type pkt_type); + +/* + * TX Packet Dequeueing Interface + */ +void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb); +bool dccp_qpolicy_full(struct sock *sk); +void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb); +struct sk_buff *dccp_qpolicy_top(struct sock *sk); +struct sk_buff *dccp_qpolicy_pop(struct sock *sk); +bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param); + +/* + * TX Packet Output and TX Timers + */ +void dccp_write_xmit(struct sock *sk); +void dccp_write_space(struct sock *sk); +void dccp_flush_write_queue(struct sock *sk, long *time_budget); + +void dccp_init_xmit_timers(struct sock *sk); static inline void dccp_clear_xmit_timers(struct sock *sk) { inet_csk_clear_xmit_timers(sk); } -extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); +unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); -extern const char *dccp_packet_name(const int type); -extern const char *dccp_state_name(const int state); +const char *dccp_packet_name(const int type); -static inline void dccp_set_state(struct sock *sk, const int state) -{ - const int oldstate = sk->sk_state; - - dccp_pr_debug("%s(%p) %-10.10s -> %s\n", - dccp_role(sk), sk, - dccp_state_name(oldstate), dccp_state_name(state)); - WARN_ON(state == oldstate); - - switch (state) { - case DCCP_OPEN: - if (oldstate != DCCP_OPEN) - DCCP_INC_STATS(DCCP_MIB_CURRESTAB); - break; - - case DCCP_CLOSED: - if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN) - DCCP_INC_STATS(DCCP_MIB_ESTABRESETS); - - sk->sk_prot->unhash(sk); - if (inet_csk(sk)->icsk_bind_hash != NULL && - !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) - inet_put_port(&dccp_hashinfo, sk); - /* fall through */ - default: - if (oldstate == DCCP_OPEN) - DCCP_DEC_STATS(DCCP_MIB_CURRESTAB); - } - - /* Change state AFTER socket is unhashed to avoid closed - * socket sitting in hash tables. - */ - sk->sk_state = state; -} +void dccp_set_state(struct sock *sk, const int state); +void dccp_done(struct sock *sk); -static inline void dccp_done(struct sock *sk) -{ - dccp_set_state(sk, DCCP_CLOSED); - dccp_clear_xmit_timers(sk); +int dccp_reqsk_init(struct request_sock *rq, struct dccp_sock const *dp, + struct sk_buff const *skb); - sk->sk_shutdown = SHUTDOWN_MASK; +int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); - if (!sock_flag(sk, SOCK_DEAD)) - sk->sk_state_change(sk); - else - inet_csk_destroy_sock(sk); -} +struct sock *dccp_create_openreq_child(struct sock *sk, + const struct request_sock *req, + const struct sk_buff *skb); -static inline void dccp_openreq_init(struct request_sock *req, - struct dccp_sock *dp, - struct sk_buff *skb) -{ - /* - * FIXME: fill in the other req fields from the DCCP options - * received - */ - inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; - inet_rsk(req)->acked = 0; - req->rcv_wnd = 0; -} +int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); -extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); - -extern struct sock *dccp_create_openreq_child(struct sock *sk, - const struct request_sock *req, - const struct sk_buff *skb); - -extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); - -extern void dccp_v4_err(struct sk_buff *skb, u32); - -extern int dccp_v4_rcv(struct sk_buff *skb); - -extern struct sock *dccp_v4_request_recv_sock(struct sock *sk, - struct sk_buff *skb, - struct request_sock *req, - struct dst_entry *dst); -extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, - struct request_sock *req, - struct request_sock **prev); - -extern int dccp_child_process(struct sock *parent, struct sock *child, - struct sk_buff *skb); -extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, - struct dccp_hdr *dh, unsigned len); -extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct dccp_hdr *dh, const unsigned len); - -extern int dccp_v4_init_sock(struct sock *sk); -extern int dccp_v4_destroy_sock(struct sock *sk); - -extern void dccp_close(struct sock *sk, long timeout); -extern struct sk_buff *dccp_make_response(struct sock *sk, - struct dst_entry *dst, - struct request_sock *req); -extern struct sk_buff *dccp_make_reset(struct sock *sk, - struct dst_entry *dst, - enum dccp_reset_codes code); - -extern int dccp_connect(struct sock *sk); -extern int dccp_disconnect(struct sock *sk, int flags); -extern void dccp_unhash(struct sock *sk); -extern int dccp_getsockopt(struct sock *sk, int level, int optname, - char __user *optval, int __user *optlen); -extern int dccp_setsockopt(struct sock *sk, int level, int optname, - char __user *optval, int optlen); -extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); -extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, - struct msghdr *msg, size_t size); -extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, - struct msghdr *msg, size_t len, int nonblock, - int flags, int *addr_len); -extern void dccp_shutdown(struct sock *sk, int how); -extern int inet_dccp_listen(struct socket *sock, int backlog); -extern unsigned int dccp_poll(struct file *file, struct socket *sock, - poll_table *wait); -extern void dccp_v4_send_check(struct sock *sk, int len, - struct sk_buff *skb); -extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, - int addr_len); - -extern int dccp_v4_checksum(const struct sk_buff *skb, - const u32 saddr, const u32 daddr); - -extern int dccp_v4_send_reset(struct sock *sk, - enum dccp_reset_codes code); -extern void dccp_send_close(struct sock *sk, const int active); -extern int dccp_invalid_packet(struct sk_buff *skb); +struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, + struct dst_entry *dst); +struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, + struct request_sock **prev); + +int dccp_child_process(struct sock *parent, struct sock *child, + struct sk_buff *skb); +int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, + struct dccp_hdr *dh, unsigned int len); +int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, + const struct dccp_hdr *dh, const unsigned int len); + +int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized); +void dccp_destroy_sock(struct sock *sk); + +void dccp_close(struct sock *sk, long timeout); +struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, + struct request_sock *req); + +int dccp_connect(struct sock *sk); +int dccp_disconnect(struct sock *sk, int flags); +int dccp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen); +int dccp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, unsigned int optlen); +#ifdef CONFIG_COMPAT +int compat_dccp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen); +int compat_dccp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, unsigned int optlen); +#endif +int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); +int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, + size_t size); +int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, + struct msghdr *msg, size_t len, int nonblock, int flags, + int *addr_len); +void dccp_shutdown(struct sock *sk, int how); +int inet_dccp_listen(struct socket *sock, int backlog); +unsigned int dccp_poll(struct file *file, struct socket *sock, + poll_table *wait); +int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); + +struct sk_buff *dccp_ctl_make_reset(struct sock *sk, struct sk_buff *skb); +int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code); +void dccp_send_close(struct sock *sk, const int active); +int dccp_invalid_packet(struct sk_buff *skb); +u32 dccp_sample_rtt(struct sock *sk, long delta); static inline int dccp_bad_service_code(const struct sock *sk, - const __u32 service) + const __be32 service) { const struct dccp_sock *dp = dccp_sk(sk); @@ -279,10 +337,29 @@ static inline int dccp_bad_service_code(const struct sock *sk, return !dccp_list_has_service(dp->dccps_service_list, service); } +/** + * dccp_skb_cb - DCCP per-packet control information + * @dccpd_type: one of %dccp_pkt_type (or unknown) + * @dccpd_ccval: CCVal field (5.1), see e.g. RFC 4342, 8.1 + * @dccpd_reset_code: one of %dccp_reset_codes + * @dccpd_reset_data: Data1..3 fields (depend on @dccpd_reset_code) + * @dccpd_opt_len: total length of all options (5.8) in the packet + * @dccpd_seq: sequence number + * @dccpd_ack_seq: acknowledgment number subheader field value + * + * This is used for transmission as well as for reception. + */ struct dccp_skb_cb { + union { + struct inet_skb_parm h4; +#if IS_ENABLED(CONFIG_IPV6) + struct inet6_skb_parm h6; +#endif + } header; __u8 dccpd_type:4; __u8 dccpd_ccval:4; - __u8 dccpd_reset_code; + __u8 dccpd_reset_code, + dccpd_reset_data[3]; __u16 dccpd_opt_len; __u64 dccpd_seq; __u64 dccpd_ack_seq; @@ -290,6 +367,7 @@ struct dccp_skb_cb { #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) +/* RFC 4340, sec. 7.7 */ static inline int dccp_non_data_packet(const struct sk_buff *skb) { const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; @@ -302,59 +380,40 @@ static inline int dccp_non_data_packet(const struct sk_buff *skb) type == DCCP_PKT_SYNCACK; } -static inline int dccp_packet_without_ack(const struct sk_buff *skb) +/* RFC 4340, sec. 7.7 */ +static inline int dccp_data_packet(const struct sk_buff *skb) { const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; - return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; + return type == DCCP_PKT_DATA || + type == DCCP_PKT_DATAACK || + type == DCCP_PKT_REQUEST || + type == DCCP_PKT_RESPONSE; } -#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1) -#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2) - -static inline void dccp_set_seqno(u64 *seqno, u64 value) +static inline int dccp_packet_without_ack(const struct sk_buff *skb) { - if (value > DCCP_MAX_SEQNO) - value -= DCCP_MAX_SEQNO + 1; - *seqno = value; -} + const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; -static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2) -{ - return ((seqno2 << 16) - (seqno1 << 16)) >> 16; + return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; } -static inline void dccp_inc_seqno(u64 *seqno) -{ - if (++*seqno > DCCP_MAX_SEQNO) - *seqno = 0; -} +#define DCCP_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2) static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss) { struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + sizeof(*dh)); - -#if defined(__LITTLE_ENDIAN_BITFIELD) - dh->dccph_seq = htonl((gss >> 32)) >> 8; -#elif defined(__BIG_ENDIAN_BITFIELD) - dh->dccph_seq = htonl((gss >> 32)); -#else -#error "Adjust your <asm/byteorder.h> defines" -#endif + dh->dccph_seq2 = 0; + dh->dccph_seq = htons((gss >> 32) & 0xfffff); dhx->dccph_seq_low = htonl(gss & 0xffffffff); } static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, const u64 gsr) { -#if defined(__LITTLE_ENDIAN_BITFIELD) - dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8; -#elif defined(__BIG_ENDIAN_BITFIELD) - dhack->dccph_ack_nr_high = htonl((gsr >> 32)); -#else -#error "Adjust your <asm/byteorder.h> defines" -#endif + dhack->dccph_reserved1 = 0; + dhack->dccph_ack_nr_high = htons(gsr >> 32); dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff); } @@ -362,86 +421,81 @@ static inline void dccp_update_gsr(struct sock *sk, u64 seq) { struct dccp_sock *dp = dccp_sk(sk); - dp->dccps_gsr = seq; - dccp_set_seqno(&dp->dccps_swl, - (dp->dccps_gsr + 1 - - (dp->dccps_options.dccpo_sequence_window / 4))); - dccp_set_seqno(&dp->dccps_swh, - (dp->dccps_gsr + - (3 * dp->dccps_options.dccpo_sequence_window) / 4)); + if (after48(seq, dp->dccps_gsr)) + dp->dccps_gsr = seq; + /* Sequence validity window depends on remote Sequence Window (7.5.1) */ + dp->dccps_swl = SUB48(ADD48(dp->dccps_gsr, 1), dp->dccps_r_seq_win / 4); + /* + * Adjust SWL so that it is not below ISR. In contrast to RFC 4340, + * 7.5.1 we perform this check beyond the initial handshake: W/W' are + * always > 32, so for the first W/W' packets in the lifetime of a + * connection we always have to adjust SWL. + * A second reason why we are doing this is that the window depends on + * the feature-remote value of Sequence Window: nothing stops the peer + * from updating this value while we are busy adjusting SWL for the + * first W packets (we would have to count from scratch again then). + * Therefore it is safer to always make sure that the Sequence Window + * is not artificially extended by a peer who grows SWL downwards by + * continually updating the feature-remote Sequence-Window. + * If sequence numbers wrap it is bad luck. But that will take a while + * (48 bit), and this measure prevents Sequence-number attacks. + */ + if (before48(dp->dccps_swl, dp->dccps_isr)) + dp->dccps_swl = dp->dccps_isr; + dp->dccps_swh = ADD48(dp->dccps_gsr, (3 * dp->dccps_r_seq_win) / 4); } static inline void dccp_update_gss(struct sock *sk, u64 seq) { struct dccp_sock *dp = dccp_sk(sk); - dp->dccps_awh = dp->dccps_gss = seq; - dccp_set_seqno(&dp->dccps_awl, - (dp->dccps_gss - - dp->dccps_options.dccpo_sequence_window + 1)); -} - -static inline int dccp_ack_pending(const struct sock *sk) -{ - const struct dccp_sock *dp = dccp_sk(sk); - return dp->dccps_timestamp_echo != 0 || -#ifdef CONFIG_IP_DCCP_ACKVEC - (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) || -#endif - inet_csk_ack_scheduled(sk); + dp->dccps_gss = seq; + /* Ack validity window depends on local Sequence Window value (7.5.1) */ + dp->dccps_awl = SUB48(ADD48(dp->dccps_gss, 1), dp->dccps_l_seq_win); + /* Adjust AWL so that it is not below ISS - see comment above for SWL */ + if (before48(dp->dccps_awl, dp->dccps_iss)) + dp->dccps_awl = dp->dccps_iss; + dp->dccps_awh = dp->dccps_gss; } -extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb); -extern void dccp_insert_option_elapsed_time(struct sock *sk, - struct sk_buff *skb, - u32 elapsed_time); -extern void dccp_insert_option_timestamp(struct sock *sk, - struct sk_buff *skb); -extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb, - unsigned char option, - const void *value, unsigned char len); - -extern struct socket *dccp_ctl_socket; - -extern void dccp_timestamp(const struct sock *sk, struct timeval *tv); - -static inline suseconds_t timeval_usecs(const struct timeval *tv) +static inline int dccp_ackvec_pending(const struct sock *sk) { - return tv->tv_sec * USEC_PER_SEC + tv->tv_usec; + return dccp_sk(sk)->dccps_hc_rx_ackvec != NULL && + !dccp_ackvec_is_empty(dccp_sk(sk)->dccps_hc_rx_ackvec); } -static inline suseconds_t timeval_delta(const struct timeval *large, - const struct timeval *small) +static inline int dccp_ack_pending(const struct sock *sk) { - time_t secs = large->tv_sec - small->tv_sec; - suseconds_t usecs = large->tv_usec - small->tv_usec; - - if (usecs < 0) { - secs--; - usecs += USEC_PER_SEC; - } - return secs * USEC_PER_SEC + usecs; + return dccp_ackvec_pending(sk) || inet_csk_ack_scheduled(sk); } -static inline void timeval_add_usecs(struct timeval *tv, - const suseconds_t usecs) +int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val); +int dccp_feat_finalise_settings(struct dccp_sock *dp); +int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq); +int dccp_feat_insert_opts(struct dccp_sock*, struct dccp_request_sock*, + struct sk_buff *skb); +int dccp_feat_activate_values(struct sock *sk, struct list_head *fn); +void dccp_feat_list_purge(struct list_head *fn_list); + +int dccp_insert_options(struct sock *sk, struct sk_buff *skb); +int dccp_insert_options_rsk(struct dccp_request_sock *, struct sk_buff *); +u32 dccp_timestamp(void); +void dccp_timestamping_init(void); +int dccp_insert_option(struct sk_buff *skb, unsigned char option, + const void *value, unsigned char len); + +#ifdef CONFIG_SYSCTL +int dccp_sysctl_init(void); +void dccp_sysctl_exit(void); +#else +static inline int dccp_sysctl_init(void) { - tv->tv_usec += usecs; - while (tv->tv_usec >= USEC_PER_SEC) { - tv->tv_sec++; - tv->tv_usec -= USEC_PER_SEC; - } + return 0; } -static inline void timeval_sub_usecs(struct timeval *tv, - const suseconds_t usecs) +static inline void dccp_sysctl_exit(void) { - tv->tv_usec -= usecs; - while (tv->tv_usec < 0) { - tv->tv_sec--; - tv->tv_usec += USEC_PER_SEC; - } } +#endif #endif /* _DCCP_H */ diff --git a/net/dccp/diag.c b/net/dccp/diag.c index 3f78c00e382..028fc43aacb 100644 --- a/net/dccp/diag.c +++ b/net/dccp/diag.c @@ -9,7 +9,6 @@ * published by the Free Software Foundation. */ -#include <linux/config.h> #include <linux/module.h> #include <linux/inet_diag.h> @@ -30,11 +29,14 @@ static void dccp_get_info(struct sock *sk, struct tcp_info *info) info->tcpi_backoff = icsk->icsk_backoff; info->tcpi_pmtu = icsk->icsk_pmtu_cookie; - if (dp->dccps_options.dccpo_send_ack_vector) + if (dp->dccps_hc_rx_ackvec != NULL) info->tcpi_options |= TCPI_OPT_SACK; - ccid_hc_rx_get_info(dp->dccps_hc_rx_ccid, sk, info); - ccid_hc_tx_get_info(dp->dccps_hc_tx_ccid, sk, info); + if (dp->dccps_hc_rx_ccid != NULL) + ccid_hc_rx_get_info(dp->dccps_hc_rx_ccid, sk, info); + + if (dp->dccps_hc_tx_ccid != NULL) + ccid_hc_tx_get_info(dp->dccps_hc_tx_ccid, sk, info); } static void dccp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, @@ -46,11 +48,23 @@ static void dccp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, dccp_get_info(sk, _info); } -static struct inet_diag_handler dccp_diag_handler = { - .idiag_hashinfo = &dccp_hashinfo, +static void dccp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, + struct inet_diag_req_v2 *r, struct nlattr *bc) +{ + inet_diag_dump_icsk(&dccp_hashinfo, skb, cb, r, bc); +} + +static int dccp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, + struct inet_diag_req_v2 *req) +{ + return inet_diag_dump_one_icsk(&dccp_hashinfo, in_skb, nlh, req); +} + +static const struct inet_diag_handler dccp_diag_handler = { + .dump = dccp_diag_dump, + .dump_one = dccp_diag_dump_one, .idiag_get_info = dccp_diag_get_info, - .idiag_type = DCCPDIAG_GETSOCK, - .idiag_info_size = sizeof(struct tcp_info), + .idiag_type = IPPROTO_DCCP, }; static int __init dccp_diag_init(void) @@ -69,3 +83,4 @@ module_exit(dccp_diag_fini); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); MODULE_DESCRIPTION("DCCP inet_diag handler"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-33 /* AF_INET - IPPROTO_DCCP */); diff --git a/net/dccp/feat.c b/net/dccp/feat.c new file mode 100644 index 00000000000..9733ddbc96c --- /dev/null +++ b/net/dccp/feat.c @@ -0,0 +1,1561 @@ +/* + * net/dccp/feat.c + * + * Feature negotiation for the DCCP protocol (RFC 4340, section 6) + * + * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk> + * Rewrote from scratch, some bits from earlier code by + * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk> + * + * + * ASSUMPTIONS + * ----------- + * o Feature negotiation is coordinated with connection setup (as in TCP), wild + * changes of parameters of an established connection are not supported. + * o Changing non-negotiable (NN) values is supported in state OPEN/PARTOPEN. + * o All currently known SP features have 1-byte quantities. If in the future + * extensions of RFCs 4340..42 define features with item lengths larger than + * one byte, a feature-specific extension of the code will be required. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#include <linux/module.h> +#include <linux/slab.h> +#include "ccid.h" +#include "feat.h" + +/* feature-specific sysctls - initialised to the defaults from RFC 4340, 6.4 */ +unsigned long sysctl_dccp_sequence_window __read_mostly = 100; +int sysctl_dccp_rx_ccid __read_mostly = 2, + sysctl_dccp_tx_ccid __read_mostly = 2; + +/* + * Feature activation handlers. + * + * These all use an u64 argument, to provide enough room for NN/SP features. At + * this stage the negotiated values have been checked to be within their range. + */ +static int dccp_hdlr_ccid(struct sock *sk, u64 ccid, bool rx) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid *new_ccid = ccid_new(ccid, sk, rx); + + if (new_ccid == NULL) + return -ENOMEM; + + if (rx) { + ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); + dp->dccps_hc_rx_ccid = new_ccid; + } else { + ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); + dp->dccps_hc_tx_ccid = new_ccid; + } + return 0; +} + +static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx) +{ + struct dccp_sock *dp = dccp_sk(sk); + + if (rx) { + dp->dccps_r_seq_win = seq_win; + /* propagate changes to update SWL/SWH */ + dccp_update_gsr(sk, dp->dccps_gsr); + } else { + dp->dccps_l_seq_win = seq_win; + /* propagate changes to update AWL */ + dccp_update_gss(sk, dp->dccps_gss); + } + return 0; +} + +static int dccp_hdlr_ack_ratio(struct sock *sk, u64 ratio, bool rx) +{ + if (rx) + dccp_sk(sk)->dccps_r_ack_ratio = ratio; + else + dccp_sk(sk)->dccps_l_ack_ratio = ratio; + return 0; +} + +static int dccp_hdlr_ackvec(struct sock *sk, u64 enable, bool rx) +{ + struct dccp_sock *dp = dccp_sk(sk); + + if (rx) { + if (enable && dp->dccps_hc_rx_ackvec == NULL) { + dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(gfp_any()); + if (dp->dccps_hc_rx_ackvec == NULL) + return -ENOMEM; + } else if (!enable) { + dccp_ackvec_free(dp->dccps_hc_rx_ackvec); + dp->dccps_hc_rx_ackvec = NULL; + } + } + return 0; +} + +static int dccp_hdlr_ndp(struct sock *sk, u64 enable, bool rx) +{ + if (!rx) + dccp_sk(sk)->dccps_send_ndp_count = (enable > 0); + return 0; +} + +/* + * Minimum Checksum Coverage is located at the RX side (9.2.1). This means that + * `rx' holds when the sending peer informs about his partial coverage via a + * ChangeR() option. In the other case, we are the sender and the receiver + * announces its coverage via ChangeL() options. The policy here is to honour + * such communication by enabling the corresponding partial coverage - but only + * if it has not been set manually before; the warning here means that all + * packets will be dropped. + */ +static int dccp_hdlr_min_cscov(struct sock *sk, u64 cscov, bool rx) +{ + struct dccp_sock *dp = dccp_sk(sk); + + if (rx) + dp->dccps_pcrlen = cscov; + else { + if (dp->dccps_pcslen == 0) + dp->dccps_pcslen = cscov; + else if (cscov > dp->dccps_pcslen) + DCCP_WARN("CsCov %u too small, peer requires >= %u\n", + dp->dccps_pcslen, (u8)cscov); + } + return 0; +} + +static const struct { + u8 feat_num; /* DCCPF_xxx */ + enum dccp_feat_type rxtx; /* RX or TX */ + enum dccp_feat_type reconciliation; /* SP or NN */ + u8 default_value; /* as in 6.4 */ + int (*activation_hdlr)(struct sock *sk, u64 val, bool rx); +/* + * Lookup table for location and type of features (from RFC 4340/4342) + * +--------------------------+----+-----+----+----+---------+-----------+ + * | Feature | Location | Reconc. | Initial | Section | + * | | RX | TX | SP | NN | Value | Reference | + * +--------------------------+----+-----+----+----+---------+-----------+ + * | DCCPF_CCID | | X | X | | 2 | 10 | + * | DCCPF_SHORT_SEQNOS | | X | X | | 0 | 7.6.1 | + * | DCCPF_SEQUENCE_WINDOW | | X | | X | 100 | 7.5.2 | + * | DCCPF_ECN_INCAPABLE | X | | X | | 0 | 12.1 | + * | DCCPF_ACK_RATIO | | X | | X | 2 | 11.3 | + * | DCCPF_SEND_ACK_VECTOR | X | | X | | 0 | 11.5 | + * | DCCPF_SEND_NDP_COUNT | | X | X | | 0 | 7.7.2 | + * | DCCPF_MIN_CSUM_COVER | X | | X | | 0 | 9.2.1 | + * | DCCPF_DATA_CHECKSUM | X | | X | | 0 | 9.3.1 | + * | DCCPF_SEND_LEV_RATE | X | | X | | 0 | 4342/8.4 | + * +--------------------------+----+-----+----+----+---------+-----------+ + */ +} dccp_feat_table[] = { + { DCCPF_CCID, FEAT_AT_TX, FEAT_SP, 2, dccp_hdlr_ccid }, + { DCCPF_SHORT_SEQNOS, FEAT_AT_TX, FEAT_SP, 0, NULL }, + { DCCPF_SEQUENCE_WINDOW, FEAT_AT_TX, FEAT_NN, 100, dccp_hdlr_seq_win }, + { DCCPF_ECN_INCAPABLE, FEAT_AT_RX, FEAT_SP, 0, NULL }, + { DCCPF_ACK_RATIO, FEAT_AT_TX, FEAT_NN, 2, dccp_hdlr_ack_ratio}, + { DCCPF_SEND_ACK_VECTOR, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_ackvec }, + { DCCPF_SEND_NDP_COUNT, FEAT_AT_TX, FEAT_SP, 0, dccp_hdlr_ndp }, + { DCCPF_MIN_CSUM_COVER, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_min_cscov}, + { DCCPF_DATA_CHECKSUM, FEAT_AT_RX, FEAT_SP, 0, NULL }, + { DCCPF_SEND_LEV_RATE, FEAT_AT_RX, FEAT_SP, 0, NULL }, +}; +#define DCCP_FEAT_SUPPORTED_MAX ARRAY_SIZE(dccp_feat_table) + +/** + * dccp_feat_index - Hash function to map feature number into array position + * Returns consecutive array index or -1 if the feature is not understood. + */ +static int dccp_feat_index(u8 feat_num) +{ + /* The first 9 entries are occupied by the types from RFC 4340, 6.4 */ + if (feat_num > DCCPF_RESERVED && feat_num <= DCCPF_DATA_CHECKSUM) + return feat_num - 1; + + /* + * Other features: add cases for new feature types here after adding + * them to the above table. + */ + switch (feat_num) { + case DCCPF_SEND_LEV_RATE: + return DCCP_FEAT_SUPPORTED_MAX - 1; + } + return -1; +} + +static u8 dccp_feat_type(u8 feat_num) +{ + int idx = dccp_feat_index(feat_num); + + if (idx < 0) + return FEAT_UNKNOWN; + return dccp_feat_table[idx].reconciliation; +} + +static int dccp_feat_default_value(u8 feat_num) +{ + int idx = dccp_feat_index(feat_num); + /* + * There are no default values for unknown features, so encountering a + * negative index here indicates a serious problem somewhere else. + */ + DCCP_BUG_ON(idx < 0); + + return idx < 0 ? 0 : dccp_feat_table[idx].default_value; +} + +/* + * Debugging and verbose-printing section + */ +static const char *dccp_feat_fname(const u8 feat) +{ + static const char *const feature_names[] = { + [DCCPF_RESERVED] = "Reserved", + [DCCPF_CCID] = "CCID", + [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos", + [DCCPF_SEQUENCE_WINDOW] = "Sequence Window", + [DCCPF_ECN_INCAPABLE] = "ECN Incapable", + [DCCPF_ACK_RATIO] = "Ack Ratio", + [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector", + [DCCPF_SEND_NDP_COUNT] = "Send NDP Count", + [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage", + [DCCPF_DATA_CHECKSUM] = "Send Data Checksum", + }; + if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC) + return feature_names[DCCPF_RESERVED]; + + if (feat == DCCPF_SEND_LEV_RATE) + return "Send Loss Event Rate"; + if (feat >= DCCPF_MIN_CCID_SPECIFIC) + return "CCID-specific"; + + return feature_names[feat]; +} + +static const char *const dccp_feat_sname[] = { + "DEFAULT", "INITIALISING", "CHANGING", "UNSTABLE", "STABLE", +}; + +#ifdef CONFIG_IP_DCCP_DEBUG +static const char *dccp_feat_oname(const u8 opt) +{ + switch (opt) { + case DCCPO_CHANGE_L: return "Change_L"; + case DCCPO_CONFIRM_L: return "Confirm_L"; + case DCCPO_CHANGE_R: return "Change_R"; + case DCCPO_CONFIRM_R: return "Confirm_R"; + } + return NULL; +} + +static void dccp_feat_printval(u8 feat_num, dccp_feat_val const *val) +{ + u8 i, type = dccp_feat_type(feat_num); + + if (val == NULL || (type == FEAT_SP && val->sp.vec == NULL)) + dccp_pr_debug_cat("(NULL)"); + else if (type == FEAT_SP) + for (i = 0; i < val->sp.len; i++) + dccp_pr_debug_cat("%s%u", i ? " " : "", val->sp.vec[i]); + else if (type == FEAT_NN) + dccp_pr_debug_cat("%llu", (unsigned long long)val->nn); + else + dccp_pr_debug_cat("unknown type %u", type); +} + +static void dccp_feat_printvals(u8 feat_num, u8 *list, u8 len) +{ + u8 type = dccp_feat_type(feat_num); + dccp_feat_val fval = { .sp.vec = list, .sp.len = len }; + + if (type == FEAT_NN) + fval.nn = dccp_decode_value_var(list, len); + dccp_feat_printval(feat_num, &fval); +} + +static void dccp_feat_print_entry(struct dccp_feat_entry const *entry) +{ + dccp_debug(" * %s %s = ", entry->is_local ? "local" : "remote", + dccp_feat_fname(entry->feat_num)); + dccp_feat_printval(entry->feat_num, &entry->val); + dccp_pr_debug_cat(", state=%s %s\n", dccp_feat_sname[entry->state], + entry->needs_confirm ? "(Confirm pending)" : ""); +} + +#define dccp_feat_print_opt(opt, feat, val, len, mandatory) do { \ + dccp_pr_debug("%s(%s, ", dccp_feat_oname(opt), dccp_feat_fname(feat));\ + dccp_feat_printvals(feat, val, len); \ + dccp_pr_debug_cat(") %s\n", mandatory ? "!" : ""); } while (0) + +#define dccp_feat_print_fnlist(fn_list) { \ + const struct dccp_feat_entry *___entry; \ + \ + dccp_pr_debug("List Dump:\n"); \ + list_for_each_entry(___entry, fn_list, node) \ + dccp_feat_print_entry(___entry); \ +} +#else /* ! CONFIG_IP_DCCP_DEBUG */ +#define dccp_feat_print_opt(opt, feat, val, len, mandatory) +#define dccp_feat_print_fnlist(fn_list) +#endif + +static int __dccp_feat_activate(struct sock *sk, const int idx, + const bool is_local, dccp_feat_val const *fval) +{ + bool rx; + u64 val; + + if (idx < 0 || idx >= DCCP_FEAT_SUPPORTED_MAX) + return -1; + if (dccp_feat_table[idx].activation_hdlr == NULL) + return 0; + + if (fval == NULL) { + val = dccp_feat_table[idx].default_value; + } else if (dccp_feat_table[idx].reconciliation == FEAT_SP) { + if (fval->sp.vec == NULL) { + /* + * This can happen when an empty Confirm is sent + * for an SP (i.e. known) feature. In this case + * we would be using the default anyway. + */ + DCCP_CRIT("Feature #%d undefined: using default", idx); + val = dccp_feat_table[idx].default_value; + } else { + val = fval->sp.vec[0]; + } + } else { + val = fval->nn; + } + + /* Location is RX if this is a local-RX or remote-TX feature */ + rx = (is_local == (dccp_feat_table[idx].rxtx == FEAT_AT_RX)); + + dccp_debug(" -> activating %s %s, %sval=%llu\n", rx ? "RX" : "TX", + dccp_feat_fname(dccp_feat_table[idx].feat_num), + fval ? "" : "default ", (unsigned long long)val); + + return dccp_feat_table[idx].activation_hdlr(sk, val, rx); +} + +/** + * dccp_feat_activate - Activate feature value on socket + * @sk: fully connected DCCP socket (after handshake is complete) + * @feat_num: feature to activate, one of %dccp_feature_numbers + * @local: whether local (1) or remote (0) @feat_num is meant + * @fval: the value (SP or NN) to activate, or NULL to use the default value + * + * For general use this function is preferable over __dccp_feat_activate(). + */ +static int dccp_feat_activate(struct sock *sk, u8 feat_num, bool local, + dccp_feat_val const *fval) +{ + return __dccp_feat_activate(sk, dccp_feat_index(feat_num), local, fval); +} + +/* Test for "Req'd" feature (RFC 4340, 6.4) */ +static inline int dccp_feat_must_be_understood(u8 feat_num) +{ + return feat_num == DCCPF_CCID || feat_num == DCCPF_SHORT_SEQNOS || + feat_num == DCCPF_SEQUENCE_WINDOW; +} + +/* copy constructor, fval must not already contain allocated memory */ +static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len) +{ + fval->sp.len = len; + if (fval->sp.len > 0) { + fval->sp.vec = kmemdup(val, len, gfp_any()); + if (fval->sp.vec == NULL) { + fval->sp.len = 0; + return -ENOBUFS; + } + } + return 0; +} + +static void dccp_feat_val_destructor(u8 feat_num, dccp_feat_val *val) +{ + if (unlikely(val == NULL)) + return; + if (dccp_feat_type(feat_num) == FEAT_SP) + kfree(val->sp.vec); + memset(val, 0, sizeof(*val)); +} + +static struct dccp_feat_entry * + dccp_feat_clone_entry(struct dccp_feat_entry const *original) +{ + struct dccp_feat_entry *new; + u8 type = dccp_feat_type(original->feat_num); + + if (type == FEAT_UNKNOWN) + return NULL; + + new = kmemdup(original, sizeof(struct dccp_feat_entry), gfp_any()); + if (new == NULL) + return NULL; + + if (type == FEAT_SP && dccp_feat_clone_sp_val(&new->val, + original->val.sp.vec, + original->val.sp.len)) { + kfree(new); + return NULL; + } + return new; +} + +static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry) +{ + if (entry != NULL) { + dccp_feat_val_destructor(entry->feat_num, &entry->val); + kfree(entry); + } +} + +/* + * List management functions + * + * Feature negotiation lists rely on and maintain the following invariants: + * - each feat_num in the list is known, i.e. we know its type and default value + * - each feat_num/is_local combination is unique (old entries are overwritten) + * - SP values are always freshly allocated + * - list is sorted in increasing order of feature number (faster lookup) + */ +static struct dccp_feat_entry *dccp_feat_list_lookup(struct list_head *fn_list, + u8 feat_num, bool is_local) +{ + struct dccp_feat_entry *entry; + + list_for_each_entry(entry, fn_list, node) { + if (entry->feat_num == feat_num && entry->is_local == is_local) + return entry; + else if (entry->feat_num > feat_num) + break; + } + return NULL; +} + +/** + * dccp_feat_entry_new - Central list update routine (called by all others) + * @head: list to add to + * @feat: feature number + * @local: whether the local (1) or remote feature with number @feat is meant + * + * This is the only constructor and serves to ensure the above invariants. + */ +static struct dccp_feat_entry * + dccp_feat_entry_new(struct list_head *head, u8 feat, bool local) +{ + struct dccp_feat_entry *entry; + + list_for_each_entry(entry, head, node) + if (entry->feat_num == feat && entry->is_local == local) { + dccp_feat_val_destructor(entry->feat_num, &entry->val); + return entry; + } else if (entry->feat_num > feat) { + head = &entry->node; + break; + } + + entry = kmalloc(sizeof(*entry), gfp_any()); + if (entry != NULL) { + entry->feat_num = feat; + entry->is_local = local; + list_add_tail(&entry->node, head); + } + return entry; +} + +/** + * dccp_feat_push_change - Add/overwrite a Change option in the list + * @fn_list: feature-negotiation list to update + * @feat: one of %dccp_feature_numbers + * @local: whether local (1) or remote (0) @feat_num is meant + * @needs_mandatory: whether to use Mandatory feature negotiation options + * @fval: pointer to NN/SP value to be inserted (will be copied) + */ +static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local, + u8 mandatory, dccp_feat_val *fval) +{ + struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local); + + if (new == NULL) + return -ENOMEM; + + new->feat_num = feat; + new->is_local = local; + new->state = FEAT_INITIALISING; + new->needs_confirm = false; + new->empty_confirm = false; + new->val = *fval; + new->needs_mandatory = mandatory; + + return 0; +} + +/** + * dccp_feat_push_confirm - Add a Confirm entry to the FN list + * @fn_list: feature-negotiation list to add to + * @feat: one of %dccp_feature_numbers + * @local: whether local (1) or remote (0) @feat_num is being confirmed + * @fval: pointer to NN/SP value to be inserted or NULL + * + * Returns 0 on success, a Reset code for further processing otherwise. + */ +static int dccp_feat_push_confirm(struct list_head *fn_list, u8 feat, u8 local, + dccp_feat_val *fval) +{ + struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local); + + if (new == NULL) + return DCCP_RESET_CODE_TOO_BUSY; + + new->feat_num = feat; + new->is_local = local; + new->state = FEAT_STABLE; /* transition in 6.6.2 */ + new->needs_confirm = true; + new->empty_confirm = (fval == NULL); + new->val.nn = 0; /* zeroes the whole structure */ + if (!new->empty_confirm) + new->val = *fval; + new->needs_mandatory = false; + + return 0; +} + +static int dccp_push_empty_confirm(struct list_head *fn_list, u8 feat, u8 local) +{ + return dccp_feat_push_confirm(fn_list, feat, local, NULL); +} + +static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry) +{ + list_del(&entry->node); + dccp_feat_entry_destructor(entry); +} + +void dccp_feat_list_purge(struct list_head *fn_list) +{ + struct dccp_feat_entry *entry, *next; + + list_for_each_entry_safe(entry, next, fn_list, node) + dccp_feat_entry_destructor(entry); + INIT_LIST_HEAD(fn_list); +} +EXPORT_SYMBOL_GPL(dccp_feat_list_purge); + +/* generate @to as full clone of @from - @to must not contain any nodes */ +int dccp_feat_clone_list(struct list_head const *from, struct list_head *to) +{ + struct dccp_feat_entry *entry, *new; + + INIT_LIST_HEAD(to); + list_for_each_entry(entry, from, node) { + new = dccp_feat_clone_entry(entry); + if (new == NULL) + goto cloning_failed; + list_add_tail(&new->node, to); + } + return 0; + +cloning_failed: + dccp_feat_list_purge(to); + return -ENOMEM; +} + +/** + * dccp_feat_valid_nn_length - Enforce length constraints on NN options + * Length is between 0 and %DCCP_OPTVAL_MAXLEN. Used for outgoing packets only, + * incoming options are accepted as long as their values are valid. + */ +static u8 dccp_feat_valid_nn_length(u8 feat_num) +{ + if (feat_num == DCCPF_ACK_RATIO) /* RFC 4340, 11.3 and 6.6.8 */ + return 2; + if (feat_num == DCCPF_SEQUENCE_WINDOW) /* RFC 4340, 7.5.2 and 6.5 */ + return 6; + return 0; +} + +static u8 dccp_feat_is_valid_nn_val(u8 feat_num, u64 val) +{ + switch (feat_num) { + case DCCPF_ACK_RATIO: + return val <= DCCPF_ACK_RATIO_MAX; + case DCCPF_SEQUENCE_WINDOW: + return val >= DCCPF_SEQ_WMIN && val <= DCCPF_SEQ_WMAX; + } + return 0; /* feature unknown - so we can't tell */ +} + +/* check that SP values are within the ranges defined in RFC 4340 */ +static u8 dccp_feat_is_valid_sp_val(u8 feat_num, u8 val) +{ + switch (feat_num) { + case DCCPF_CCID: + return val == DCCPC_CCID2 || val == DCCPC_CCID3; + /* Type-check Boolean feature values: */ + case DCCPF_SHORT_SEQNOS: + case DCCPF_ECN_INCAPABLE: + case DCCPF_SEND_ACK_VECTOR: + case DCCPF_SEND_NDP_COUNT: + case DCCPF_DATA_CHECKSUM: + case DCCPF_SEND_LEV_RATE: + return val < 2; + case DCCPF_MIN_CSUM_COVER: + return val < 16; + } + return 0; /* feature unknown */ +} + +static u8 dccp_feat_sp_list_ok(u8 feat_num, u8 const *sp_list, u8 sp_len) +{ + if (sp_list == NULL || sp_len < 1) + return 0; + while (sp_len--) + if (!dccp_feat_is_valid_sp_val(feat_num, *sp_list++)) + return 0; + return 1; +} + +/** + * dccp_feat_insert_opts - Generate FN options from current list state + * @skb: next sk_buff to be sent to the peer + * @dp: for client during handshake and general negotiation + * @dreq: used by the server only (all Changes/Confirms in LISTEN/RESPOND) + */ +int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq, + struct sk_buff *skb) +{ + struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg; + struct dccp_feat_entry *pos, *next; + u8 opt, type, len, *ptr, nn_in_nbo[DCCP_OPTVAL_MAXLEN]; + bool rpt; + + /* put entries into @skb in the order they appear in the list */ + list_for_each_entry_safe_reverse(pos, next, fn, node) { + opt = dccp_feat_genopt(pos); + type = dccp_feat_type(pos->feat_num); + rpt = false; + + if (pos->empty_confirm) { + len = 0; + ptr = NULL; + } else { + if (type == FEAT_SP) { + len = pos->val.sp.len; + ptr = pos->val.sp.vec; + rpt = pos->needs_confirm; + } else if (type == FEAT_NN) { + len = dccp_feat_valid_nn_length(pos->feat_num); + ptr = nn_in_nbo; + dccp_encode_value_var(pos->val.nn, ptr, len); + } else { + DCCP_BUG("unknown feature %u", pos->feat_num); + return -1; + } + } + dccp_feat_print_opt(opt, pos->feat_num, ptr, len, 0); + + if (dccp_insert_fn_opt(skb, opt, pos->feat_num, ptr, len, rpt)) + return -1; + if (pos->needs_mandatory && dccp_insert_option_mandatory(skb)) + return -1; + + if (skb->sk->sk_state == DCCP_OPEN && + (opt == DCCPO_CONFIRM_R || opt == DCCPO_CONFIRM_L)) { + /* + * Confirms don't get retransmitted (6.6.3) once the + * connection is in state OPEN + */ + dccp_feat_list_pop(pos); + } else { + /* + * Enter CHANGING after transmitting the Change + * option (6.6.2). + */ + if (pos->state == FEAT_INITIALISING) + pos->state = FEAT_CHANGING; + } + } + return 0; +} + +/** + * __feat_register_nn - Register new NN value on socket + * @fn: feature-negotiation list to register with + * @feat: an NN feature from %dccp_feature_numbers + * @mandatory: use Mandatory option if 1 + * @nn_val: value to register (restricted to 4 bytes) + * + * Note that NN features are local by definition (RFC 4340, 6.3.2). + */ +static int __feat_register_nn(struct list_head *fn, u8 feat, + u8 mandatory, u64 nn_val) +{ + dccp_feat_val fval = { .nn = nn_val }; + + if (dccp_feat_type(feat) != FEAT_NN || + !dccp_feat_is_valid_nn_val(feat, nn_val)) + return -EINVAL; + + /* Don't bother with default values, they will be activated anyway. */ + if (nn_val - (u64)dccp_feat_default_value(feat) == 0) + return 0; + + return dccp_feat_push_change(fn, feat, 1, mandatory, &fval); +} + +/** + * __feat_register_sp - Register new SP value/list on socket + * @fn: feature-negotiation list to register with + * @feat: an SP feature from %dccp_feature_numbers + * @is_local: whether the local (1) or the remote (0) @feat is meant + * @mandatory: use Mandatory option if 1 + * @sp_val: SP value followed by optional preference list + * @sp_len: length of @sp_val in bytes + */ +static int __feat_register_sp(struct list_head *fn, u8 feat, u8 is_local, + u8 mandatory, u8 const *sp_val, u8 sp_len) +{ + dccp_feat_val fval; + + if (dccp_feat_type(feat) != FEAT_SP || + !dccp_feat_sp_list_ok(feat, sp_val, sp_len)) + return -EINVAL; + + /* Avoid negotiating alien CCIDs by only advertising supported ones */ + if (feat == DCCPF_CCID && !ccid_support_check(sp_val, sp_len)) + return -EOPNOTSUPP; + + if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len)) + return -ENOMEM; + + return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval); +} + +/** + * dccp_feat_register_sp - Register requests to change SP feature values + * @sk: client or listening socket + * @feat: one of %dccp_feature_numbers + * @is_local: whether the local (1) or remote (0) @feat is meant + * @list: array of preferred values, in descending order of preference + * @len: length of @list in bytes + */ +int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local, + u8 const *list, u8 len) +{ /* any changes must be registered before establishing the connection */ + if (sk->sk_state != DCCP_CLOSED) + return -EISCONN; + if (dccp_feat_type(feat) != FEAT_SP) + return -EINVAL; + return __feat_register_sp(&dccp_sk(sk)->dccps_featneg, feat, is_local, + 0, list, len); +} + +/** + * dccp_feat_nn_get - Query current/pending value of NN feature + * @sk: DCCP socket of an established connection + * @feat: NN feature number from %dccp_feature_numbers + * + * For a known NN feature, returns value currently being negotiated, or + * current (confirmed) value if no negotiation is going on. + */ +u64 dccp_feat_nn_get(struct sock *sk, u8 feat) +{ + if (dccp_feat_type(feat) == FEAT_NN) { + struct dccp_sock *dp = dccp_sk(sk); + struct dccp_feat_entry *entry; + + entry = dccp_feat_list_lookup(&dp->dccps_featneg, feat, 1); + if (entry != NULL) + return entry->val.nn; + + switch (feat) { + case DCCPF_ACK_RATIO: + return dp->dccps_l_ack_ratio; + case DCCPF_SEQUENCE_WINDOW: + return dp->dccps_l_seq_win; + } + } + DCCP_BUG("attempt to look up unsupported feature %u", feat); + return 0; +} +EXPORT_SYMBOL_GPL(dccp_feat_nn_get); + +/** + * dccp_feat_signal_nn_change - Update NN values for an established connection + * @sk: DCCP socket of an established connection + * @feat: NN feature number from %dccp_feature_numbers + * @nn_val: the new value to use + * + * This function is used to communicate NN updates out-of-band. + */ +int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val) +{ + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + dccp_feat_val fval = { .nn = nn_val }; + struct dccp_feat_entry *entry; + + if (sk->sk_state != DCCP_OPEN && sk->sk_state != DCCP_PARTOPEN) + return 0; + + if (dccp_feat_type(feat) != FEAT_NN || + !dccp_feat_is_valid_nn_val(feat, nn_val)) + return -EINVAL; + + if (nn_val == dccp_feat_nn_get(sk, feat)) + return 0; /* already set or negotiation under way */ + + entry = dccp_feat_list_lookup(fn, feat, 1); + if (entry != NULL) { + dccp_pr_debug("Clobbering existing NN entry %llu -> %llu\n", + (unsigned long long)entry->val.nn, + (unsigned long long)nn_val); + dccp_feat_list_pop(entry); + } + + inet_csk_schedule_ack(sk); + return dccp_feat_push_change(fn, feat, 1, 0, &fval); +} +EXPORT_SYMBOL_GPL(dccp_feat_signal_nn_change); + +/* + * Tracking features whose value depend on the choice of CCID + * + * This is designed with an extension in mind so that a list walk could be done + * before activating any features. However, the existing framework was found to + * work satisfactorily up until now, the automatic verification is left open. + * When adding new CCIDs, add a corresponding dependency table here. + */ +static const struct ccid_dependency *dccp_feat_ccid_deps(u8 ccid, bool is_local) +{ + static const struct ccid_dependency ccid2_dependencies[2][2] = { + /* + * CCID2 mandates Ack Vectors (RFC 4341, 4.): as CCID is a TX + * feature and Send Ack Vector is an RX feature, `is_local' + * needs to be reversed. + */ + { /* Dependencies of the receiver-side (remote) CCID2 */ + { + .dependent_feat = DCCPF_SEND_ACK_VECTOR, + .is_local = true, + .is_mandatory = true, + .val = 1 + }, + { 0, 0, 0, 0 } + }, + { /* Dependencies of the sender-side (local) CCID2 */ + { + .dependent_feat = DCCPF_SEND_ACK_VECTOR, + .is_local = false, + .is_mandatory = true, + .val = 1 + }, + { 0, 0, 0, 0 } + } + }; + static const struct ccid_dependency ccid3_dependencies[2][5] = { + { /* + * Dependencies of the receiver-side CCID3 + */ + { /* locally disable Ack Vectors */ + .dependent_feat = DCCPF_SEND_ACK_VECTOR, + .is_local = true, + .is_mandatory = false, + .val = 0 + }, + { /* see below why Send Loss Event Rate is on */ + .dependent_feat = DCCPF_SEND_LEV_RATE, + .is_local = true, + .is_mandatory = true, + .val = 1 + }, + { /* NDP Count is needed as per RFC 4342, 6.1.1 */ + .dependent_feat = DCCPF_SEND_NDP_COUNT, + .is_local = false, + .is_mandatory = true, + .val = 1 + }, + { 0, 0, 0, 0 }, + }, + { /* + * CCID3 at the TX side: we request that the HC-receiver + * will not send Ack Vectors (they will be ignored, so + * Mandatory is not set); we enable Send Loss Event Rate + * (Mandatory since the implementation does not support + * the Loss Intervals option of RFC 4342, 8.6). + * The last two options are for peer's information only. + */ + { + .dependent_feat = DCCPF_SEND_ACK_VECTOR, + .is_local = false, + .is_mandatory = false, + .val = 0 + }, + { + .dependent_feat = DCCPF_SEND_LEV_RATE, + .is_local = false, + .is_mandatory = true, + .val = 1 + }, + { /* this CCID does not support Ack Ratio */ + .dependent_feat = DCCPF_ACK_RATIO, + .is_local = true, + .is_mandatory = false, + .val = 0 + }, + { /* tell receiver we are sending NDP counts */ + .dependent_feat = DCCPF_SEND_NDP_COUNT, + .is_local = true, + .is_mandatory = false, + .val = 1 + }, + { 0, 0, 0, 0 } + } + }; + switch (ccid) { + case DCCPC_CCID2: + return ccid2_dependencies[is_local]; + case DCCPC_CCID3: + return ccid3_dependencies[is_local]; + default: + return NULL; + } +} + +/** + * dccp_feat_propagate_ccid - Resolve dependencies of features on choice of CCID + * @fn: feature-negotiation list to update + * @id: CCID number to track + * @is_local: whether TX CCID (1) or RX CCID (0) is meant + * + * This function needs to be called after registering all other features. + */ +static int dccp_feat_propagate_ccid(struct list_head *fn, u8 id, bool is_local) +{ + const struct ccid_dependency *table = dccp_feat_ccid_deps(id, is_local); + int i, rc = (table == NULL); + + for (i = 0; rc == 0 && table[i].dependent_feat != DCCPF_RESERVED; i++) + if (dccp_feat_type(table[i].dependent_feat) == FEAT_SP) + rc = __feat_register_sp(fn, table[i].dependent_feat, + table[i].is_local, + table[i].is_mandatory, + &table[i].val, 1); + else + rc = __feat_register_nn(fn, table[i].dependent_feat, + table[i].is_mandatory, + table[i].val); + return rc; +} + +/** + * dccp_feat_finalise_settings - Finalise settings before starting negotiation + * @dp: client or listening socket (settings will be inherited) + * + * This is called after all registrations (socket initialisation, sysctls, and + * sockopt calls), and before sending the first packet containing Change options + * (ie. client-Request or server-Response), to ensure internal consistency. + */ +int dccp_feat_finalise_settings(struct dccp_sock *dp) +{ + struct list_head *fn = &dp->dccps_featneg; + struct dccp_feat_entry *entry; + int i = 2, ccids[2] = { -1, -1 }; + + /* + * Propagating CCIDs: + * 1) not useful to propagate CCID settings if this host advertises more + * than one CCID: the choice of CCID may still change - if this is + * the client, or if this is the server and the client sends + * singleton CCID values. + * 2) since is that propagate_ccid changes the list, we defer changing + * the sorted list until after the traversal. + */ + list_for_each_entry(entry, fn, node) + if (entry->feat_num == DCCPF_CCID && entry->val.sp.len == 1) + ccids[entry->is_local] = entry->val.sp.vec[0]; + while (i--) + if (ccids[i] > 0 && dccp_feat_propagate_ccid(fn, ccids[i], i)) + return -1; + dccp_feat_print_fnlist(fn); + return 0; +} + +/** + * dccp_feat_server_ccid_dependencies - Resolve CCID-dependent features + * It is the server which resolves the dependencies once the CCID has been + * fully negotiated. If no CCID has been negotiated, it uses the default CCID. + */ +int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq) +{ + struct list_head *fn = &dreq->dreq_featneg; + struct dccp_feat_entry *entry; + u8 is_local, ccid; + + for (is_local = 0; is_local <= 1; is_local++) { + entry = dccp_feat_list_lookup(fn, DCCPF_CCID, is_local); + + if (entry != NULL && !entry->empty_confirm) + ccid = entry->val.sp.vec[0]; + else + ccid = dccp_feat_default_value(DCCPF_CCID); + + if (dccp_feat_propagate_ccid(fn, ccid, is_local)) + return -1; + } + return 0; +} + +/* Select the first entry in @servlist that also occurs in @clilist (6.3.1) */ +static int dccp_feat_preflist_match(u8 *servlist, u8 slen, u8 *clilist, u8 clen) +{ + u8 c, s; + + for (s = 0; s < slen; s++) + for (c = 0; c < clen; c++) + if (servlist[s] == clilist[c]) + return servlist[s]; + return -1; +} + +/** + * dccp_feat_prefer - Move preferred entry to the start of array + * Reorder the @array_len elements in @array so that @preferred_value comes + * first. Returns >0 to indicate that @preferred_value does occur in @array. + */ +static u8 dccp_feat_prefer(u8 preferred_value, u8 *array, u8 array_len) +{ + u8 i, does_occur = 0; + + if (array != NULL) { + for (i = 0; i < array_len; i++) + if (array[i] == preferred_value) { + array[i] = array[0]; + does_occur++; + } + if (does_occur) + array[0] = preferred_value; + } + return does_occur; +} + +/** + * dccp_feat_reconcile - Reconcile SP preference lists + * @fval: SP list to reconcile into + * @arr: received SP preference list + * @len: length of @arr in bytes + * @is_server: whether this side is the server (and @fv is the server's list) + * @reorder: whether to reorder the list in @fv after reconciling with @arr + * When successful, > 0 is returned and the reconciled list is in @fval. + * A value of 0 means that negotiation failed (no shared entry). + */ +static int dccp_feat_reconcile(dccp_feat_val *fv, u8 *arr, u8 len, + bool is_server, bool reorder) +{ + int rc; + + if (!fv->sp.vec || !arr) { + DCCP_CRIT("NULL feature value or array"); + return 0; + } + + if (is_server) + rc = dccp_feat_preflist_match(fv->sp.vec, fv->sp.len, arr, len); + else + rc = dccp_feat_preflist_match(arr, len, fv->sp.vec, fv->sp.len); + + if (!reorder) + return rc; + if (rc < 0) + return 0; + + /* + * Reorder list: used for activating features and in dccp_insert_fn_opt. + */ + return dccp_feat_prefer(rc, fv->sp.vec, fv->sp.len); +} + +/** + * dccp_feat_change_recv - Process incoming ChangeL/R options + * @fn: feature-negotiation list to update + * @is_mandatory: whether the Change was preceded by a Mandatory option + * @opt: %DCCPO_CHANGE_L or %DCCPO_CHANGE_R + * @feat: one of %dccp_feature_numbers + * @val: NN value or SP value/preference list + * @len: length of @val in bytes + * @server: whether this node is the server (1) or the client (0) + */ +static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt, + u8 feat, u8 *val, u8 len, const bool server) +{ + u8 defval, type = dccp_feat_type(feat); + const bool local = (opt == DCCPO_CHANGE_R); + struct dccp_feat_entry *entry; + dccp_feat_val fval; + + if (len == 0 || type == FEAT_UNKNOWN) /* 6.1 and 6.6.8 */ + goto unknown_feature_or_value; + + dccp_feat_print_opt(opt, feat, val, len, is_mandatory); + + /* + * Negotiation of NN features: Change R is invalid, so there is no + * simultaneous negotiation; hence we do not look up in the list. + */ + if (type == FEAT_NN) { + if (local || len > sizeof(fval.nn)) + goto unknown_feature_or_value; + + /* 6.3.2: "The feature remote MUST accept any valid value..." */ + fval.nn = dccp_decode_value_var(val, len); + if (!dccp_feat_is_valid_nn_val(feat, fval.nn)) + goto unknown_feature_or_value; + + return dccp_feat_push_confirm(fn, feat, local, &fval); + } + + /* + * Unidirectional/simultaneous negotiation of SP features (6.3.1) + */ + entry = dccp_feat_list_lookup(fn, feat, local); + if (entry == NULL) { + /* + * No particular preferences have been registered. We deal with + * this situation by assuming that all valid values are equally + * acceptable, and apply the following checks: + * - if the peer's list is a singleton, we accept a valid value; + * - if we are the server, we first try to see if the peer (the + * client) advertises the default value. If yes, we use it, + * otherwise we accept the preferred value; + * - else if we are the client, we use the first list element. + */ + if (dccp_feat_clone_sp_val(&fval, val, 1)) + return DCCP_RESET_CODE_TOO_BUSY; + + if (len > 1 && server) { + defval = dccp_feat_default_value(feat); + if (dccp_feat_preflist_match(&defval, 1, val, len) > -1) + fval.sp.vec[0] = defval; + } else if (!dccp_feat_is_valid_sp_val(feat, fval.sp.vec[0])) { + kfree(fval.sp.vec); + goto unknown_feature_or_value; + } + + /* Treat unsupported CCIDs like invalid values */ + if (feat == DCCPF_CCID && !ccid_support_check(fval.sp.vec, 1)) { + kfree(fval.sp.vec); + goto not_valid_or_not_known; + } + + return dccp_feat_push_confirm(fn, feat, local, &fval); + + } else if (entry->state == FEAT_UNSTABLE) { /* 6.6.2 */ + return 0; + } + + if (dccp_feat_reconcile(&entry->val, val, len, server, true)) { + entry->empty_confirm = false; + } else if (is_mandatory) { + return DCCP_RESET_CODE_MANDATORY_ERROR; + } else if (entry->state == FEAT_INITIALISING) { + /* + * Failed simultaneous negotiation (server only): try to `save' + * the connection by checking whether entry contains the default + * value for @feat. If yes, send an empty Confirm to signal that + * the received Change was not understood - which implies using + * the default value. + * If this also fails, we use Reset as the last resort. + */ + WARN_ON(!server); + defval = dccp_feat_default_value(feat); + if (!dccp_feat_reconcile(&entry->val, &defval, 1, server, true)) + return DCCP_RESET_CODE_OPTION_ERROR; + entry->empty_confirm = true; + } + entry->needs_confirm = true; + entry->needs_mandatory = false; + entry->state = FEAT_STABLE; + return 0; + +unknown_feature_or_value: + if (!is_mandatory) + return dccp_push_empty_confirm(fn, feat, local); + +not_valid_or_not_known: + return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR + : DCCP_RESET_CODE_OPTION_ERROR; +} + +/** + * dccp_feat_confirm_recv - Process received Confirm options + * @fn: feature-negotiation list to update + * @is_mandatory: whether @opt was preceded by a Mandatory option + * @opt: %DCCPO_CONFIRM_L or %DCCPO_CONFIRM_R + * @feat: one of %dccp_feature_numbers + * @val: NN value or SP value/preference list + * @len: length of @val in bytes + * @server: whether this node is server (1) or client (0) + */ +static u8 dccp_feat_confirm_recv(struct list_head *fn, u8 is_mandatory, u8 opt, + u8 feat, u8 *val, u8 len, const bool server) +{ + u8 *plist, plen, type = dccp_feat_type(feat); + const bool local = (opt == DCCPO_CONFIRM_R); + struct dccp_feat_entry *entry = dccp_feat_list_lookup(fn, feat, local); + + dccp_feat_print_opt(opt, feat, val, len, is_mandatory); + + if (entry == NULL) { /* nothing queued: ignore or handle error */ + if (is_mandatory && type == FEAT_UNKNOWN) + return DCCP_RESET_CODE_MANDATORY_ERROR; + + if (!local && type == FEAT_NN) /* 6.3.2 */ + goto confirmation_failed; + return 0; + } + + if (entry->state != FEAT_CHANGING) /* 6.6.2 */ + return 0; + + if (len == 0) { + if (dccp_feat_must_be_understood(feat)) /* 6.6.7 */ + goto confirmation_failed; + /* + * Empty Confirm during connection setup: this means reverting + * to the `old' value, which in this case is the default. Since + * we handle default values automatically when no other values + * have been set, we revert to the old value by removing this + * entry from the list. + */ + dccp_feat_list_pop(entry); + return 0; + } + + if (type == FEAT_NN) { + if (len > sizeof(entry->val.nn)) + goto confirmation_failed; + + if (entry->val.nn == dccp_decode_value_var(val, len)) + goto confirmation_succeeded; + + DCCP_WARN("Bogus Confirm for non-existing value\n"); + goto confirmation_failed; + } + + /* + * Parsing SP Confirms: the first element of @val is the preferred + * SP value which the peer confirms, the remainder depends on @len. + * Note that only the confirmed value need to be a valid SP value. + */ + if (!dccp_feat_is_valid_sp_val(feat, *val)) + goto confirmation_failed; + + if (len == 1) { /* peer didn't supply a preference list */ + plist = val; + plen = len; + } else { /* preferred value + preference list */ + plist = val + 1; + plen = len - 1; + } + + /* Check whether the peer got the reconciliation right (6.6.8) */ + if (dccp_feat_reconcile(&entry->val, plist, plen, server, 0) != *val) { + DCCP_WARN("Confirm selected the wrong value %u\n", *val); + return DCCP_RESET_CODE_OPTION_ERROR; + } + entry->val.sp.vec[0] = *val; + +confirmation_succeeded: + entry->state = FEAT_STABLE; + return 0; + +confirmation_failed: + DCCP_WARN("Confirmation failed\n"); + return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR + : DCCP_RESET_CODE_OPTION_ERROR; +} + +/** + * dccp_feat_handle_nn_established - Fast-path reception of NN options + * @sk: socket of an established DCCP connection + * @mandatory: whether @opt was preceded by a Mandatory option + * @opt: %DCCPO_CHANGE_L | %DCCPO_CONFIRM_R (NN only) + * @feat: NN number, one of %dccp_feature_numbers + * @val: NN value + * @len: length of @val in bytes + * + * This function combines the functionality of change_recv/confirm_recv, with + * the following differences (reset codes are the same): + * - cleanup after receiving the Confirm; + * - values are directly activated after successful parsing; + * - deliberately restricted to NN features. + * The restriction to NN features is essential since SP features can have non- + * predictable outcomes (depending on the remote configuration), and are inter- + * dependent (CCIDs for instance cause further dependencies). + */ +static u8 dccp_feat_handle_nn_established(struct sock *sk, u8 mandatory, u8 opt, + u8 feat, u8 *val, u8 len) +{ + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + const bool local = (opt == DCCPO_CONFIRM_R); + struct dccp_feat_entry *entry; + u8 type = dccp_feat_type(feat); + dccp_feat_val fval; + + dccp_feat_print_opt(opt, feat, val, len, mandatory); + + /* Ignore non-mandatory unknown and non-NN features */ + if (type == FEAT_UNKNOWN) { + if (local && !mandatory) + return 0; + goto fast_path_unknown; + } else if (type != FEAT_NN) { + return 0; + } + + /* + * We don't accept empty Confirms, since in fast-path feature + * negotiation the values are enabled immediately after sending + * the Change option. + * Empty Changes on the other hand are invalid (RFC 4340, 6.1). + */ + if (len == 0 || len > sizeof(fval.nn)) + goto fast_path_unknown; + + if (opt == DCCPO_CHANGE_L) { + fval.nn = dccp_decode_value_var(val, len); + if (!dccp_feat_is_valid_nn_val(feat, fval.nn)) + goto fast_path_unknown; + + if (dccp_feat_push_confirm(fn, feat, local, &fval) || + dccp_feat_activate(sk, feat, local, &fval)) + return DCCP_RESET_CODE_TOO_BUSY; + + /* set the `Ack Pending' flag to piggyback a Confirm */ + inet_csk_schedule_ack(sk); + + } else if (opt == DCCPO_CONFIRM_R) { + entry = dccp_feat_list_lookup(fn, feat, local); + if (entry == NULL || entry->state != FEAT_CHANGING) + return 0; + + fval.nn = dccp_decode_value_var(val, len); + /* + * Just ignore a value that doesn't match our current value. + * If the option changes twice within two RTTs, then at least + * one CONFIRM will be received for the old value after a + * new CHANGE was sent. + */ + if (fval.nn != entry->val.nn) + return 0; + + /* Only activate after receiving the Confirm option (6.6.1). */ + dccp_feat_activate(sk, feat, local, &fval); + + /* It has been confirmed - so remove the entry */ + dccp_feat_list_pop(entry); + + } else { + DCCP_WARN("Received illegal option %u\n", opt); + goto fast_path_failed; + } + return 0; + +fast_path_unknown: + if (!mandatory) + return dccp_push_empty_confirm(fn, feat, local); + +fast_path_failed: + return mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR + : DCCP_RESET_CODE_OPTION_ERROR; +} + +/** + * dccp_feat_parse_options - Process Feature-Negotiation Options + * @sk: for general use and used by the client during connection setup + * @dreq: used by the server during connection setup + * @mandatory: whether @opt was preceded by a Mandatory option + * @opt: %DCCPO_CHANGE_L | %DCCPO_CHANGE_R | %DCCPO_CONFIRM_L | %DCCPO_CONFIRM_R + * @feat: one of %dccp_feature_numbers + * @val: value contents of @opt + * @len: length of @val in bytes + * + * Returns 0 on success, a Reset code for ending the connection otherwise. + */ +int dccp_feat_parse_options(struct sock *sk, struct dccp_request_sock *dreq, + u8 mandatory, u8 opt, u8 feat, u8 *val, u8 len) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg; + bool server = false; + + switch (sk->sk_state) { + /* + * Negotiation during connection setup + */ + case DCCP_LISTEN: + server = true; /* fall through */ + case DCCP_REQUESTING: + switch (opt) { + case DCCPO_CHANGE_L: + case DCCPO_CHANGE_R: + return dccp_feat_change_recv(fn, mandatory, opt, feat, + val, len, server); + case DCCPO_CONFIRM_R: + case DCCPO_CONFIRM_L: + return dccp_feat_confirm_recv(fn, mandatory, opt, feat, + val, len, server); + } + break; + /* + * Support for exchanging NN options on an established connection. + */ + case DCCP_OPEN: + case DCCP_PARTOPEN: + return dccp_feat_handle_nn_established(sk, mandatory, opt, feat, + val, len); + } + return 0; /* ignore FN options in all other states */ +} + +/** + * dccp_feat_init - Seed feature negotiation with host-specific defaults + * This initialises global defaults, depending on the value of the sysctls. + * These can later be overridden by registering changes via setsockopt calls. + * The last link in the chain is finalise_settings, to make sure that between + * here and the start of actual feature negotiation no inconsistencies enter. + * + * All features not appearing below use either defaults or are otherwise + * later adjusted through dccp_feat_finalise_settings(). + */ +int dccp_feat_init(struct sock *sk) +{ + struct list_head *fn = &dccp_sk(sk)->dccps_featneg; + u8 on = 1, off = 0; + int rc; + struct { + u8 *val; + u8 len; + } tx, rx; + + /* Non-negotiable (NN) features */ + rc = __feat_register_nn(fn, DCCPF_SEQUENCE_WINDOW, 0, + sysctl_dccp_sequence_window); + if (rc) + return rc; + + /* Server-priority (SP) features */ + + /* Advertise that short seqnos are not supported (7.6.1) */ + rc = __feat_register_sp(fn, DCCPF_SHORT_SEQNOS, true, true, &off, 1); + if (rc) + return rc; + + /* RFC 4340 12.1: "If a DCCP is not ECN capable, ..." */ + rc = __feat_register_sp(fn, DCCPF_ECN_INCAPABLE, true, true, &on, 1); + if (rc) + return rc; + + /* + * We advertise the available list of CCIDs and reorder according to + * preferences, to avoid failure resulting from negotiating different + * singleton values (which always leads to failure). + * These settings can still (later) be overridden via sockopts. + */ + if (ccid_get_builtin_ccids(&tx.val, &tx.len) || + ccid_get_builtin_ccids(&rx.val, &rx.len)) + return -ENOBUFS; + + if (!dccp_feat_prefer(sysctl_dccp_tx_ccid, tx.val, tx.len) || + !dccp_feat_prefer(sysctl_dccp_rx_ccid, rx.val, rx.len)) + goto free_ccid_lists; + + rc = __feat_register_sp(fn, DCCPF_CCID, true, false, tx.val, tx.len); + if (rc) + goto free_ccid_lists; + + rc = __feat_register_sp(fn, DCCPF_CCID, false, false, rx.val, rx.len); + +free_ccid_lists: + kfree(tx.val); + kfree(rx.val); + return rc; +} + +int dccp_feat_activate_values(struct sock *sk, struct list_head *fn_list) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct dccp_feat_entry *cur, *next; + int idx; + dccp_feat_val *fvals[DCCP_FEAT_SUPPORTED_MAX][2] = { + [0 ... DCCP_FEAT_SUPPORTED_MAX-1] = { NULL, NULL } + }; + + list_for_each_entry(cur, fn_list, node) { + /* + * An empty Confirm means that either an unknown feature type + * or an invalid value was present. In the first case there is + * nothing to activate, in the other the default value is used. + */ + if (cur->empty_confirm) + continue; + + idx = dccp_feat_index(cur->feat_num); + if (idx < 0) { + DCCP_BUG("Unknown feature %u", cur->feat_num); + goto activation_failed; + } + if (cur->state != FEAT_STABLE) { + DCCP_CRIT("Negotiation of %s %s failed in state %s", + cur->is_local ? "local" : "remote", + dccp_feat_fname(cur->feat_num), + dccp_feat_sname[cur->state]); + goto activation_failed; + } + fvals[idx][cur->is_local] = &cur->val; + } + + /* + * Activate in decreasing order of index, so that the CCIDs are always + * activated as the last feature. This avoids the case where a CCID + * relies on the initialisation of one or more features that it depends + * on (e.g. Send NDP Count, Send Ack Vector, and Ack Ratio features). + */ + for (idx = DCCP_FEAT_SUPPORTED_MAX; --idx >= 0;) + if (__dccp_feat_activate(sk, idx, 0, fvals[idx][0]) || + __dccp_feat_activate(sk, idx, 1, fvals[idx][1])) { + DCCP_CRIT("Could not activate %d", idx); + goto activation_failed; + } + + /* Clean up Change options which have been confirmed already */ + list_for_each_entry_safe(cur, next, fn_list, node) + if (!cur->needs_confirm) + dccp_feat_list_pop(cur); + + dccp_pr_debug("Activation OK\n"); + return 0; + +activation_failed: + /* + * We clean up everything that may have been allocated, since + * it is difficult to track at which stage negotiation failed. + * This is ok, since all allocation functions below are robust + * against NULL arguments. + */ + ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); + ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); + dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL; + dccp_ackvec_free(dp->dccps_hc_rx_ackvec); + dp->dccps_hc_rx_ackvec = NULL; + return -1; +} diff --git a/net/dccp/feat.h b/net/dccp/feat.h new file mode 100644 index 00000000000..0e75cebb218 --- /dev/null +++ b/net/dccp/feat.h @@ -0,0 +1,137 @@ +#ifndef _DCCP_FEAT_H +#define _DCCP_FEAT_H +/* + * net/dccp/feat.h + * + * Feature negotiation for the DCCP protocol (RFC 4340, section 6) + * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk> + * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/types.h> +#include "dccp.h" + +/* + * Known limit values + */ +/* Ack Ratio takes 2-byte integer values (11.3) */ +#define DCCPF_ACK_RATIO_MAX 0xFFFF +/* Wmin=32 and Wmax=2^46-1 from 7.5.2 */ +#define DCCPF_SEQ_WMIN 32 +#define DCCPF_SEQ_WMAX 0x3FFFFFFFFFFFull +/* Maximum number of SP values that fit in a single (Confirm) option */ +#define DCCP_FEAT_MAX_SP_VALS (DCCP_SINGLE_OPT_MAXLEN - 2) + +enum dccp_feat_type { + FEAT_AT_RX = 1, /* located at RX side of half-connection */ + FEAT_AT_TX = 2, /* located at TX side of half-connection */ + FEAT_SP = 4, /* server-priority reconciliation (6.3.1) */ + FEAT_NN = 8, /* non-negotiable reconciliation (6.3.2) */ + FEAT_UNKNOWN = 0xFF /* not understood or invalid feature */ +}; + +enum dccp_feat_state { + FEAT_DEFAULT = 0, /* using default values from 6.4 */ + FEAT_INITIALISING, /* feature is being initialised */ + FEAT_CHANGING, /* Change sent but not confirmed yet */ + FEAT_UNSTABLE, /* local modification in state CHANGING */ + FEAT_STABLE /* both ends (think they) agree */ +}; + +/** + * dccp_feat_val - Container for SP or NN feature values + * @nn: single NN value + * @sp.vec: single SP value plus optional preference list + * @sp.len: length of @sp.vec in bytes + */ +typedef union { + u64 nn; + struct { + u8 *vec; + u8 len; + } sp; +} dccp_feat_val; + +/** + * struct feat_entry - Data structure to perform feature negotiation + * @val: feature's current value (SP features may have preference list) + * @state: feature's current state + * @feat_num: one of %dccp_feature_numbers + * @needs_mandatory: whether Mandatory options should be sent + * @needs_confirm: whether to send a Confirm instead of a Change + * @empty_confirm: whether to send an empty Confirm (depends on @needs_confirm) + * @is_local: feature location (1) or feature-remote (0) + * @node: list pointers, entries arranged in FIFO order + */ +struct dccp_feat_entry { + dccp_feat_val val; + enum dccp_feat_state state:8; + u8 feat_num; + + bool needs_mandatory, + needs_confirm, + empty_confirm, + is_local; + + struct list_head node; +}; + +static inline u8 dccp_feat_genopt(struct dccp_feat_entry *entry) +{ + if (entry->needs_confirm) + return entry->is_local ? DCCPO_CONFIRM_L : DCCPO_CONFIRM_R; + return entry->is_local ? DCCPO_CHANGE_L : DCCPO_CHANGE_R; +} + +/** + * struct ccid_dependency - Track changes resulting from choosing a CCID + * @dependent_feat: one of %dccp_feature_numbers + * @is_local: local (1) or remote (0) @dependent_feat + * @is_mandatory: whether presence of @dependent_feat is mission-critical or not + * @val: corresponding default value for @dependent_feat (u8 is sufficient here) + */ +struct ccid_dependency { + u8 dependent_feat; + bool is_local:1, + is_mandatory:1; + u8 val; +}; + +/* + * Sysctls to seed defaults for feature negotiation + */ +extern unsigned long sysctl_dccp_sequence_window; +extern int sysctl_dccp_rx_ccid; +extern int sysctl_dccp_tx_ccid; + +int dccp_feat_init(struct sock *sk); +void dccp_feat_initialise_sysctls(void); +int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local, + u8 const *list, u8 len); +int dccp_feat_parse_options(struct sock *, struct dccp_request_sock *, + u8 mand, u8 opt, u8 feat, u8 *val, u8 len); +int dccp_feat_clone_list(struct list_head const *, struct list_head *); + +/* + * Encoding variable-length options and their maximum length. + * + * This affects NN options (SP options are all u8) and other variable-length + * options (see table 3 in RFC 4340). The limit is currently given the Sequence + * Window NN value (sec. 7.5.2) and the NDP count (sec. 7.7) option, all other + * options consume less than 6 bytes (timestamps are 4 bytes). + * When updating this constant (e.g. due to new internet drafts / RFCs), make + * sure that you also update all code which refers to it. + */ +#define DCCP_OPTVAL_MAXLEN 6 + +void dccp_encode_value_var(const u64 value, u8 *to, const u8 len); +u64 dccp_decode_value_var(const u8 *bf, const u8 len); +u64 dccp_feat_nn_get(struct sock *sk, u8 feat); + +int dccp_insert_option_mandatory(struct sk_buff *skb); +int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat, u8 *val, u8 len, + bool repeat_first); +#endif /* _DCCP_FEAT_H */ diff --git a/net/dccp/input.c b/net/dccp/input.c index b6cba72b44e..3c8ec7d4a34 100644 --- a/net/dccp/input.c +++ b/net/dccp/input.c @@ -1,6 +1,6 @@ /* * net/dccp/input.c - * + * * An implementation of the DCCP protocol * Arnaldo Carvalho de Melo <acme@conectiva.com.br> * @@ -10,9 +10,9 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/skbuff.h> +#include <linux/slab.h> #include <net/sock.h> @@ -20,26 +20,80 @@ #include "ccid.h" #include "dccp.h" -static void dccp_fin(struct sock *sk, struct sk_buff *skb) +/* rate-limit for syncs in reply to sequence-invalid packets; RFC 4340, 7.5.4 */ +int sysctl_dccp_sync_ratelimit __read_mostly = HZ / 8; + +static void dccp_enqueue_skb(struct sock *sk, struct sk_buff *skb) { - sk->sk_shutdown |= RCV_SHUTDOWN; - sock_set_flag(sk, SOCK_DONE); __skb_pull(skb, dccp_hdr(skb)->dccph_doff * 4); __skb_queue_tail(&sk->sk_receive_queue, skb); skb_set_owner_r(skb, sk); - sk->sk_data_ready(sk, 0); + sk->sk_data_ready(sk); } -static void dccp_rcv_close(struct sock *sk, struct sk_buff *skb) +static void dccp_fin(struct sock *sk, struct sk_buff *skb) { - dccp_v4_send_reset(sk, DCCP_RESET_CODE_CLOSED); - dccp_fin(sk, skb); - dccp_set_state(sk, DCCP_CLOSED); - sk_wake_async(sk, 1, POLL_HUP); + /* + * On receiving Close/CloseReq, both RD/WR shutdown are performed. + * RFC 4340, 8.3 says that we MAY send further Data/DataAcks after + * receiving the closing segment, but there is no guarantee that such + * data will be processed at all. + */ + sk->sk_shutdown = SHUTDOWN_MASK; + sock_set_flag(sk, SOCK_DONE); + dccp_enqueue_skb(sk, skb); } -static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) +static int dccp_rcv_close(struct sock *sk, struct sk_buff *skb) { + int queued = 0; + + switch (sk->sk_state) { + /* + * We ignore Close when received in one of the following states: + * - CLOSED (may be a late or duplicate packet) + * - PASSIVE_CLOSEREQ (the peer has sent a CloseReq earlier) + * - RESPOND (already handled by dccp_check_req) + */ + case DCCP_CLOSING: + /* + * Simultaneous-close: receiving a Close after sending one. This + * can happen if both client and server perform active-close and + * will result in an endless ping-pong of crossing and retrans- + * mitted Close packets, which only terminates when one of the + * nodes times out (min. 64 seconds). Quicker convergence can be + * achieved when one of the nodes acts as tie-breaker. + * This is ok as both ends are done with data transfer and each + * end is just waiting for the other to acknowledge termination. + */ + if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) + break; + /* fall through */ + case DCCP_REQUESTING: + case DCCP_ACTIVE_CLOSEREQ: + dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); + dccp_done(sk); + break; + case DCCP_OPEN: + case DCCP_PARTOPEN: + /* Give waiting application a chance to read pending data */ + queued = 1; + dccp_fin(sk, skb); + dccp_set_state(sk, DCCP_PASSIVE_CLOSE); + /* fall through */ + case DCCP_PASSIVE_CLOSE: + /* + * Retransmitted Close: we have already enqueued the first one. + */ + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); + } + return queued; +} + +static int dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) +{ + int queued = 0; + /* * Step 7: Check for unexpected packet types * If (S.is_server and P.type == CloseReq) @@ -48,28 +102,96 @@ static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) */ if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) { dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC); - return; + return queued; } - if (sk->sk_state != DCCP_CLOSING) + /* Step 13: process relevant Client states < CLOSEREQ */ + switch (sk->sk_state) { + case DCCP_REQUESTING: + dccp_send_close(sk, 0); dccp_set_state(sk, DCCP_CLOSING); - dccp_send_close(sk, 0); + break; + case DCCP_OPEN: + case DCCP_PARTOPEN: + /* Give waiting application a chance to read pending data */ + queued = 1; + dccp_fin(sk, skb); + dccp_set_state(sk, DCCP_PASSIVE_CLOSEREQ); + /* fall through */ + case DCCP_PASSIVE_CLOSEREQ: + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); + } + return queued; } -static inline void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb) +static u16 dccp_reset_code_convert(const u8 code) { - struct dccp_sock *dp = dccp_sk(sk); + const u16 error_code[] = { + [DCCP_RESET_CODE_CLOSED] = 0, /* normal termination */ + [DCCP_RESET_CODE_UNSPECIFIED] = 0, /* nothing known */ + [DCCP_RESET_CODE_ABORTED] = ECONNRESET, + + [DCCP_RESET_CODE_NO_CONNECTION] = ECONNREFUSED, + [DCCP_RESET_CODE_CONNECTION_REFUSED] = ECONNREFUSED, + [DCCP_RESET_CODE_TOO_BUSY] = EUSERS, + [DCCP_RESET_CODE_AGGRESSION_PENALTY] = EDQUOT, + + [DCCP_RESET_CODE_PACKET_ERROR] = ENOMSG, + [DCCP_RESET_CODE_BAD_INIT_COOKIE] = EBADR, + [DCCP_RESET_CODE_BAD_SERVICE_CODE] = EBADRQC, + [DCCP_RESET_CODE_OPTION_ERROR] = EILSEQ, + [DCCP_RESET_CODE_MANDATORY_ERROR] = EOPNOTSUPP, + }; + + return code >= DCCP_MAX_RESET_CODES ? 0 : error_code[code]; +} + +static void dccp_rcv_reset(struct sock *sk, struct sk_buff *skb) +{ + u16 err = dccp_reset_code_convert(dccp_hdr_reset(skb)->dccph_reset_code); - if (dp->dccps_options.dccpo_send_ack_vector) - dccp_ackvec_check_rcv_ackno(dp->dccps_hc_rx_ackvec, sk, - DCCP_SKB_CB(skb)->dccpd_ack_seq); + sk->sk_err = err; + + /* Queue the equivalent of TCP fin so that dccp_recvmsg exits the loop */ + dccp_fin(sk, skb); + + if (err && !sock_flag(sk, SOCK_DEAD)) + sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); + dccp_time_wait(sk, DCCP_TIME_WAIT, 0); +} + +static void dccp_handle_ackvec_processing(struct sock *sk, struct sk_buff *skb) +{ + struct dccp_ackvec *av = dccp_sk(sk)->dccps_hc_rx_ackvec; + + if (av == NULL) + return; + if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) + dccp_ackvec_clear_state(av, DCCP_SKB_CB(skb)->dccpd_ack_seq); + dccp_ackvec_input(av, skb); +} + +static void dccp_deliver_input_to_ccids(struct sock *sk, struct sk_buff *skb) +{ + const struct dccp_sock *dp = dccp_sk(sk); + + /* Don't deliver to RX CCID when node has shut down read end. */ + if (!(sk->sk_shutdown & RCV_SHUTDOWN)) + ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); + /* + * Until the TX queue has been drained, we can not honour SHUT_WR, since + * we need received feedback as input to adjust congestion control. + */ + if (sk->sk_write_queue.qlen > 0 || !(sk->sk_shutdown & SEND_SHUTDOWN)) + ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); } static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb) { const struct dccp_hdr *dh = dccp_hdr(skb); struct dccp_sock *dp = dccp_sk(sk); - u64 lswl, lawl; + u64 lswl, lawl, seqno = DCCP_SKB_CB(skb)->dccpd_seq, + ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; /* * Step 5: Prepare sequence numbers for Sync @@ -83,16 +205,15 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb) * Otherwise, * Drop packet and return */ - if (dh->dccph_type == DCCP_PKT_SYNC || + if (dh->dccph_type == DCCP_PKT_SYNC || dh->dccph_type == DCCP_PKT_SYNCACK) { - if (between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, - dp->dccps_awl, dp->dccps_awh) && - !before48(DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_swl)) - dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq); + if (between48(ackno, dp->dccps_awl, dp->dccps_awh) && + dccp_delta_seqno(dp->dccps_swl, seqno) >= 0) + dccp_update_gsr(sk, seqno); else return -1; } - + /* * Step 6: Check sequence numbers * Let LSWL = S.SWL and LAWL = S.AWL @@ -103,9 +224,6 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb) * Update S.GSR, S.SWL, S.SWH * If P.type != Sync, * Update S.GAR - * Otherwise, - * Send Sync packet acknowledging P.seqno - * Drop packet and return */ lswl = dp->dccps_swl; lawl = dp->dccps_awl; @@ -113,47 +231,61 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb) if (dh->dccph_type == DCCP_PKT_CLOSEREQ || dh->dccph_type == DCCP_PKT_CLOSE || dh->dccph_type == DCCP_PKT_RESET) { - lswl = dp->dccps_gsr; - dccp_inc_seqno(&lswl); + lswl = ADD48(dp->dccps_gsr, 1); lawl = dp->dccps_gar; } - if (between48(DCCP_SKB_CB(skb)->dccpd_seq, lswl, dp->dccps_swh) && - (DCCP_SKB_CB(skb)->dccpd_ack_seq == DCCP_PKT_WITHOUT_ACK_SEQ || - between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, - lawl, dp->dccps_awh))) { - dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq); + if (between48(seqno, lswl, dp->dccps_swh) && + (ackno == DCCP_PKT_WITHOUT_ACK_SEQ || + between48(ackno, lawl, dp->dccps_awh))) { + dccp_update_gsr(sk, seqno); if (dh->dccph_type != DCCP_PKT_SYNC && - (DCCP_SKB_CB(skb)->dccpd_ack_seq != - DCCP_PKT_WITHOUT_ACK_SEQ)) - dp->dccps_gar = DCCP_SKB_CB(skb)->dccpd_ack_seq; + ackno != DCCP_PKT_WITHOUT_ACK_SEQ && + after48(ackno, dp->dccps_gar)) + dp->dccps_gar = ackno; } else { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: Step 6 failed for %s packet, " - "(LSWL(%llu) <= P.seqno(%llu) <= S.SWH(%llu)) and " - "(P.ackno %s or LAWL(%llu) <= P.ackno(%llu) <= S.AWH(%llu), " - "sending SYNC...\n", - dccp_packet_name(dh->dccph_type), - (unsigned long long) lswl, - (unsigned long long) - DCCP_SKB_CB(skb)->dccpd_seq, - (unsigned long long) dp->dccps_swh, - (DCCP_SKB_CB(skb)->dccpd_ack_seq == - DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist" : "exists", - (unsigned long long) lawl, - (unsigned long long) - DCCP_SKB_CB(skb)->dccpd_ack_seq, - (unsigned long long) dp->dccps_awh); - dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC); + unsigned long now = jiffies; + /* + * Step 6: Check sequence numbers + * Otherwise, + * If P.type == Reset, + * Send Sync packet acknowledging S.GSR + * Otherwise, + * Send Sync packet acknowledging P.seqno + * Drop packet and return + * + * These Syncs are rate-limited as per RFC 4340, 7.5.4: + * at most 1 / (dccp_sync_rate_limit * HZ) Syncs per second. + */ + if (time_before(now, (dp->dccps_rate_last + + sysctl_dccp_sync_ratelimit))) + return -1; + + DCCP_WARN("Step 6 failed for %s packet, " + "(LSWL(%llu) <= P.seqno(%llu) <= S.SWH(%llu)) and " + "(P.ackno %s or LAWL(%llu) <= P.ackno(%llu) <= S.AWH(%llu), " + "sending SYNC...\n", dccp_packet_name(dh->dccph_type), + (unsigned long long) lswl, (unsigned long long) seqno, + (unsigned long long) dp->dccps_swh, + (ackno == DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist" + : "exists", + (unsigned long long) lawl, (unsigned long long) ackno, + (unsigned long long) dp->dccps_awh); + + dp->dccps_rate_last = now; + + if (dh->dccph_type == DCCP_PKT_RESET) + seqno = dp->dccps_gsr; + dccp_send_sync(sk, seqno, DCCP_PKT_SYNC); return -1; } return 0; } -static inline int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct dccp_hdr *dh, - const unsigned len) +static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, + const struct dccp_hdr *dh, const unsigned int len) { struct dccp_sock *dp = dccp_sk(sk); @@ -161,13 +293,11 @@ static inline int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, case DCCP_PKT_DATAACK: case DCCP_PKT_DATA: /* - * FIXME: check if sk_receive_queue is full, schedule DATA_DROPPED - * option if it is. + * FIXME: schedule DATA_DROPPED (RFC 4340, 11.7.2) if and when + * - sk_shutdown == RCV_SHUTDOWN, use Code 1, "Not Listening" + * - sk_receive_queue is full, use Code 2, "Receive Buffer" */ - __skb_pull(skb, dh->dccph_doff * 4); - __skb_queue_tail(&sk->sk_receive_queue, skb); - skb_set_owner_r(skb, sk); - sk->sk_data_ready(sk, 0); + dccp_enqueue_skb(sk, skb); return 0; case DCCP_PKT_ACK: goto discard; @@ -179,19 +309,20 @@ static inline int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, * S.state := TIMEWAIT * Set TIMEWAIT timer * Drop packet and return - */ - dccp_fin(sk, skb); - dccp_time_wait(sk, DCCP_TIME_WAIT, 0); + */ + dccp_rcv_reset(sk, skb); return 0; case DCCP_PKT_CLOSEREQ: - dccp_rcv_closereq(sk, skb); + if (dccp_rcv_closereq(sk, skb)) + return 0; goto discard; case DCCP_PKT_CLOSE: - dccp_rcv_close(sk, skb); - return 0; + if (dccp_rcv_close(sk, skb)) + return 0; + goto discard; case DCCP_PKT_REQUEST: - /* Step 7 - * or (S.is_server and P.type == Response) + /* Step 7 + * or (S.is_server and P.type == Response) * or (S.is_client and P.type == Request) * or (S.state >= OPEN and P.type == Request * and P.seqno >= S.OSR) @@ -208,7 +339,8 @@ static inline int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, if (dp->dccps_role != DCCP_ROLE_CLIENT) goto send_sync; check_seq: - if (!before48(DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_osr)) { + if (dccp_delta_seqno(dp->dccps_osr, + DCCP_SKB_CB(skb)->dccpd_seq) >= 0) { send_sync: dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC); @@ -218,11 +350,11 @@ send_sync: dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNCACK); /* - * From the draft: + * From RFC 4340, sec. 5.7 * * As with DCCP-Ack packets, DCCP-Sync and DCCP-SyncAck packets * MAY have non-zero-length application data areas, whose - * contents * receivers MUST ignore. + * contents receivers MUST ignore. */ goto discard; } @@ -234,27 +366,16 @@ discard: } int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct dccp_hdr *dh, const unsigned len) + const struct dccp_hdr *dh, const unsigned int len) { - struct dccp_sock *dp = dccp_sk(sk); - if (dccp_check_seqno(sk, skb)) goto discard; - if (dccp_parse_options(sk, skb)) - goto discard; - - if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) - dccp_event_ack_recv(sk, skb); - - if (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, - DCCP_SKB_CB(skb)->dccpd_seq, - DCCP_ACKVEC_STATE_RECEIVED)) - goto discard; + if (dccp_parse_options(sk, NULL, skb)) + return 1; - ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); - ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); + dccp_handle_ackvec_processing(sk, skb); + dccp_deliver_input_to_ccids(sk, skb); return __dccp_rcv_established(sk, skb, dh, len); discard: @@ -267,9 +388,9 @@ EXPORT_SYMBOL_GPL(dccp_rcv_established); static int dccp_rcv_request_sent_state_process(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, - const unsigned len) + const unsigned int len) { - /* + /* * Step 4: Prepare sequence numbers in REQUEST * If S.state == REQUEST, * If (P.type == Response or P.type == Reset) @@ -283,51 +404,45 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, if (dh->dccph_type == DCCP_PKT_RESPONSE) { const struct inet_connection_sock *icsk = inet_csk(sk); struct dccp_sock *dp = dccp_sk(sk); - - /* Stop the REQUEST timer */ - inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); - BUG_TRAP(sk->sk_send_head != NULL); - __kfree_skb(sk->sk_send_head); - sk->sk_send_head = NULL; + long tstamp = dccp_timestamp(); if (!between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, dp->dccps_awl, dp->dccps_awh)) { dccp_pr_debug("invalid ackno: S.AWL=%llu, " - "P.ackno=%llu, S.AWH=%llu \n", + "P.ackno=%llu, S.AWH=%llu\n", (unsigned long long)dp->dccps_awl, (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq, (unsigned long long)dp->dccps_awh); goto out_invalid_packet; } - if (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, - DCCP_SKB_CB(skb)->dccpd_seq, - DCCP_ACKVEC_STATE_RECEIVED)) - goto out_invalid_packet; /* FIXME: change error code */ + /* + * If option processing (Step 8) failed, return 1 here so that + * dccp_v4_do_rcv() sends a Reset. The Reset code depends on + * the option type and is set in dccp_parse_options(). + */ + if (dccp_parse_options(sk, NULL, skb)) + return 1; + + /* Obtain usec RTT sample from SYN exchange (used by TFRC). */ + if (likely(dp->dccps_options_received.dccpor_timestamp_echo)) + dp->dccps_syn_rtt = dccp_sample_rtt(sk, 10 * (tstamp - + dp->dccps_options_received.dccpor_timestamp_echo)); + + /* Stop the REQUEST timer */ + inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); + WARN_ON(sk->sk_send_head == NULL); + kfree_skb(sk->sk_send_head); + sk->sk_send_head = NULL; - dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq; - dccp_update_gsr(sk, dp->dccps_isr); /* - * SWL and AWL are initially adjusted so that they are not less than - * the initial Sequence Numbers received and sent, respectively: - * SWL := max(GSR + 1 - floor(W/4), ISR), - * AWL := max(GSS - W' + 1, ISS). - * These adjustments MUST be applied only at the beginning of the - * connection. - * - * AWL was adjusted in dccp_v4_connect -acme + * Set ISR, GSR from packet. ISS was set in dccp_v{4,6}_connect + * and GSS in dccp_transmit_skb(). Setting AWL/AWH and SWL/SWH + * is done as part of activating the feature values below, since + * these settings depend on the local/remote Sequence Window + * features, which were undefined or not confirmed until now. */ - dccp_set_seqno(&dp->dccps_swl, - max48(dp->dccps_swl, dp->dccps_isr)); - - if (ccid_hc_rx_init(dp->dccps_hc_rx_ccid, sk) != 0 || - ccid_hc_tx_init(dp->dccps_hc_tx_ccid, sk) != 0) { - ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk); - ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk); - /* FIXME: send appropriate RESET code */ - goto out_invalid_packet; - } + dp->dccps_gsr = dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq; dccp_sync_mss(sk, icsk->icsk_pmtu_cookie); @@ -342,18 +457,27 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, * from the Response * / * S.state := PARTOPEN * Set PARTOPEN timer - * Continue with S.state == PARTOPEN + * Continue with S.state == PARTOPEN * / * Step 12 will send the Ack completing the * three-way handshake * / */ dccp_set_state(sk, DCCP_PARTOPEN); + /* + * If feature negotiation was successful, activate features now; + * an activation failure means that this host could not activate + * one ore more features (e.g. insufficient memory), which would + * leave at least one feature in an undefined state. + */ + if (dccp_feat_activate_values(sk, &dp->dccps_featneg)) + goto unable_to_proceed; + /* Make sure socket is routed, for correct metrics. */ icsk->icsk_af_ops->rebuild_header(sk); if (!sock_flag(sk, SOCK_DEAD)) { sk->sk_state_change(sk); - sk_wake_async(sk, 0, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); } if (sk->sk_write_pending || icsk->icsk_ack.pingpong || @@ -373,7 +497,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, */ __kfree_skb(skb); return 0; - } + } dccp_send_ack(sk); return -1; } @@ -381,14 +505,26 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, out_invalid_packet: /* dccp_v4_do_rcv will send a reset */ DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR; - return 1; + return 1; + +unable_to_proceed: + DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_ABORTED; + /* + * We mark this socket as no longer usable, so that the loop in + * dccp_sendmsg() terminates and the application gets notified. + */ + dccp_set_state(sk, DCCP_CLOSED); + sk->sk_err = ECOMM; + return 1; } static int dccp_rcv_respond_partopen_state_process(struct sock *sk, struct sk_buff *skb, const struct dccp_hdr *dh, - const unsigned len) + const unsigned int len) { + struct dccp_sock *dp = dccp_sk(sk); + u32 sample = dp->dccps_options_received.dccpor_timestamp_echo; int queued = 0; switch (dh->dccph_type) { @@ -413,7 +549,14 @@ static int dccp_rcv_respond_partopen_state_process(struct sock *sk, if (sk->sk_state == DCCP_PARTOPEN) inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); - dccp_sk(sk)->dccps_osr = DCCP_SKB_CB(skb)->dccpd_seq; + /* Obtain usec RTT sample from SYN exchange (used by TFRC). */ + if (likely(sample)) { + long delta = dccp_timestamp() - sample; + + dp->dccps_syn_rtt = dccp_sample_rtt(sk, 10 * delta); + } + + dp->dccps_osr = DCCP_SKB_CB(skb)->dccpd_seq; dccp_set_state(sk, DCCP_OPEN); if (dh->dccph_type == DCCP_PKT_DATAACK || @@ -429,7 +572,7 @@ static int dccp_rcv_respond_partopen_state_process(struct sock *sk, } int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, - struct dccp_hdr *dh, unsigned len) + struct dccp_hdr *dh, unsigned int len) { struct dccp_sock *dp = dccp_sk(sk); struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); @@ -438,37 +581,31 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, /* * Step 3: Process LISTEN state - * (Continuing from dccp_v4_do_rcv and dccp_v6_do_rcv) * * If S.state == LISTEN, - * If P.type == Request or P contains a valid Init Cookie - * option, - * * Must scan the packet's options to check for an Init - * Cookie. Only the Init Cookie is processed here, - * however; other options are processed in Step 8. This - * scan need only be performed if the endpoint uses Init - * Cookies * - * * Generate a new socket and switch to that socket * - * Set S := new socket for this port pair - * S.state = RESPOND - * Choose S.ISS (initial seqno) or set from Init Cookie - * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie - * Continue with S.state == RESPOND - * * A Response packet will be generated in Step 11 * - * Otherwise, - * Generate Reset(No Connection) unless P.type == Reset - * Drop packet and return - * - * NOTE: the check for the packet types is done in - * dccp_rcv_state_process + * If P.type == Request or P contains a valid Init Cookie option, + * (* Must scan the packet's options to check for Init + * Cookies. Only Init Cookies are processed here, + * however; other options are processed in Step 8. This + * scan need only be performed if the endpoint uses Init + * Cookies *) + * (* Generate a new socket and switch to that socket *) + * Set S := new socket for this port pair + * S.state = RESPOND + * Choose S.ISS (initial seqno) or set from Init Cookies + * Initialize S.GAR := S.ISS + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init + * Cookies Continue with S.state == RESPOND + * (* A Response packet will be generated in Step 11 *) + * Otherwise, + * Generate Reset(No Connection) unless P.type == Reset + * Drop packet and return */ if (sk->sk_state == DCCP_LISTEN) { if (dh->dccph_type == DCCP_PKT_REQUEST) { if (inet_csk(sk)->icsk_af_ops->conn_request(sk, skb) < 0) return 1; - - /* FIXME: do congestion control initialization */ goto discard; } if (dh->dccph_type == DCCP_PKT_RESET) @@ -477,31 +614,36 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, /* Caller (dccp_v4_do_rcv) will send Reset */ dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; return 1; + } else if (sk->sk_state == DCCP_CLOSED) { + dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; + return 1; } - if (sk->sk_state != DCCP_REQUESTING) { - if (dccp_check_seqno(sk, skb)) - goto discard; - - /* - * Step 8: Process options and mark acknowledgeable - */ - if (dccp_parse_options(sk, skb)) - goto discard; - - if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) - dccp_event_ack_recv(sk, skb); - - if (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, - DCCP_SKB_CB(skb)->dccpd_seq, - DCCP_ACKVEC_STATE_RECEIVED)) - goto discard; + /* Step 6: Check sequence numbers (omitted in LISTEN/REQUEST state) */ + if (sk->sk_state != DCCP_REQUESTING && dccp_check_seqno(sk, skb)) + goto discard; - ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb); - ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb); + /* + * Step 7: Check for unexpected packet types + * If (S.is_server and P.type == Response) + * or (S.is_client and P.type == Request) + * or (S.state == RESPOND and P.type == Data), + * Send Sync packet acknowledging P.seqno + * Drop packet and return + */ + if ((dp->dccps_role != DCCP_ROLE_CLIENT && + dh->dccph_type == DCCP_PKT_RESPONSE) || + (dp->dccps_role == DCCP_ROLE_CLIENT && + dh->dccph_type == DCCP_PKT_REQUEST) || + (sk->sk_state == DCCP_RESPOND && dh->dccph_type == DCCP_PKT_DATA)) { + dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC); + goto discard; } + /* Step 8: Process options */ + if (dccp_parse_options(sk, NULL, skb)) + return 1; + /* * Step 9: Process Reset * If P.type == Reset, @@ -509,54 +651,22 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, * S.state := TIMEWAIT * Set TIMEWAIT timer * Drop packet and return - */ + */ if (dh->dccph_type == DCCP_PKT_RESET) { - /* - * Queue the equivalent of TCP fin so that dccp_recvmsg - * exits the loop - */ - dccp_fin(sk, skb); - dccp_time_wait(sk, DCCP_TIME_WAIT, 0); + dccp_rcv_reset(sk, skb); return 0; - /* - * Step 7: Check for unexpected packet types - * If (S.is_server and P.type == CloseReq) - * or (S.is_server and P.type == Response) - * or (S.is_client and P.type == Request) - * or (S.state == RESPOND and P.type == Data), - * Send Sync packet acknowledging P.seqno - * Drop packet and return - */ - } else if ((dp->dccps_role != DCCP_ROLE_CLIENT && - (dh->dccph_type == DCCP_PKT_RESPONSE || - dh->dccph_type == DCCP_PKT_CLOSEREQ)) || - (dp->dccps_role == DCCP_ROLE_CLIENT && - dh->dccph_type == DCCP_PKT_REQUEST) || - (sk->sk_state == DCCP_RESPOND && - dh->dccph_type == DCCP_PKT_DATA)) { - dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC); - goto discard; - } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) { - dccp_rcv_closereq(sk, skb); + } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) { /* Step 13 */ + if (dccp_rcv_closereq(sk, skb)) + return 0; goto discard; - } else if (dh->dccph_type == DCCP_PKT_CLOSE) { - dccp_rcv_close(sk, skb); - return 0; - } - - if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) { - dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNCACK); + } else if (dh->dccph_type == DCCP_PKT_CLOSE) { /* Step 14 */ + if (dccp_rcv_close(sk, skb)) + return 0; goto discard; } switch (sk->sk_state) { - case DCCP_CLOSED: - dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; - return 1; - case DCCP_REQUESTING: - /* FIXME: do congestion control initialization */ - queued = dccp_rcv_request_sent_state_process(sk, skb, dh, len); if (queued >= 0) return queued; @@ -564,8 +674,12 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, __kfree_skb(skb); return 0; - case DCCP_RESPOND: case DCCP_PARTOPEN: + /* Step 8: if using Ack Vectors, mark packet acknowledgeable */ + dccp_handle_ackvec_processing(sk, skb); + dccp_deliver_input_to_ccids(sk, skb); + /* fall through */ + case DCCP_RESPOND: queued = dccp_rcv_respond_partopen_state_process(sk, skb, dh, len); break; @@ -576,12 +690,15 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, switch (old_state) { case DCCP_PARTOPEN: sk->sk_state_change(sk); - sk_wake_async(sk, 0, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); break; } + } else if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) { + dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNCACK); + goto discard; } - if (!queued) { + if (!queued) { discard: __kfree_skb(skb); } @@ -589,3 +706,27 @@ discard: } EXPORT_SYMBOL_GPL(dccp_rcv_state_process); + +/** + * dccp_sample_rtt - Validate and finalise computation of RTT sample + * @delta: number of microseconds between packet and acknowledgment + * + * The routine is kept generic to work in different contexts. It should be + * called immediately when the ACK used for the RTT sample arrives. + */ +u32 dccp_sample_rtt(struct sock *sk, long delta) +{ + /* dccpor_elapsed_time is either zeroed out or set and > 0 */ + delta -= dccp_sk(sk)->dccps_options_received.dccpor_elapsed_time * 10; + + if (unlikely(delta <= 0)) { + DCCP_WARN("unusable RTT sample %ld, using min\n", delta); + return DCCP_SANE_RTT_MIN; + } + if (unlikely(delta > DCCP_SANE_RTT_MAX)) { + DCCP_WARN("RTT sample %ld too large, using max\n", delta); + return DCCP_SANE_RTT_MAX; + } + + return delta; +} diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 00f98322667..6ca645c4b48 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -10,66 +10,49 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/icmp.h> +#include <linux/slab.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/random.h> #include <net/icmp.h> +#include <net/inet_common.h> #include <net/inet_hashtables.h> #include <net/inet_sock.h> +#include <net/protocol.h> #include <net/sock.h> #include <net/timewait_sock.h> #include <net/tcp_states.h> #include <net/xfrm.h> +#include <net/secure_seq.h> #include "ackvec.h" #include "ccid.h" #include "dccp.h" +#include "feat.h" -struct inet_hashinfo __cacheline_aligned dccp_hashinfo = { - .lhash_lock = RW_LOCK_UNLOCKED, - .lhash_users = ATOMIC_INIT(0), - .lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(dccp_hashinfo.lhash_wait), -}; - -EXPORT_SYMBOL_GPL(dccp_hashinfo); - -static int dccp_v4_get_port(struct sock *sk, const unsigned short snum) -{ - return inet_csk_get_port(&dccp_hashinfo, sk, snum, - inet_csk_bind_conflict); -} - -static void dccp_v4_hash(struct sock *sk) -{ - inet_hash(&dccp_hashinfo, sk); -} - -void dccp_unhash(struct sock *sk) -{ - inet_unhash(&dccp_hashinfo, sk); -} - -EXPORT_SYMBOL_GPL(dccp_unhash); +/* + * The per-net dccp.v4_ctl_sk socket is used for responding to + * the Out-of-the-blue (OOTB) packets. A control sock will be created + * for this socket at the initialization time. + */ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { + const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; struct inet_sock *inet = inet_sk(sk); struct dccp_sock *dp = dccp_sk(sk); - const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; + __be16 orig_sport, orig_dport; + __be32 daddr, nexthop; + struct flowi4 *fl4; struct rtable *rt; - u32 daddr, nexthop; - int tmp; int err; + struct ip_options_rcu *inet_opt; dp->dccps_role = DCCP_ROLE_CLIENT; - if (dccp_service_not_initialized(sk)) - return -EPROTO; - if (addr_len < sizeof(struct sockaddr_in)) return -EINVAL; @@ -77,37 +60,43 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) return -EAFNOSUPPORT; nexthop = daddr = usin->sin_addr.s_addr; - if (inet->opt != NULL && inet->opt->srr) { + + inet_opt = rcu_dereference_protected(inet->inet_opt, + sock_owned_by_user(sk)); + if (inet_opt != NULL && inet_opt->opt.srr) { if (daddr == 0) return -EINVAL; - nexthop = inet->opt->faddr; + nexthop = inet_opt->opt.faddr; } - tmp = ip_route_connect(&rt, nexthop, inet->saddr, - RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, - IPPROTO_DCCP, - inet->sport, usin->sin_port, sk); - if (tmp < 0) - return tmp; + orig_sport = inet->inet_sport; + orig_dport = usin->sin_port; + fl4 = &inet->cork.fl.u.ip4; + rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, + RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, + IPPROTO_DCCP, + orig_sport, orig_dport, sk); + if (IS_ERR(rt)) + return PTR_ERR(rt); if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { ip_rt_put(rt); return -ENETUNREACH; } - if (inet->opt == NULL || !inet->opt->srr) - daddr = rt->rt_dst; + if (inet_opt == NULL || !inet_opt->opt.srr) + daddr = fl4->daddr; - if (inet->saddr == 0) - inet->saddr = rt->rt_src; - inet->rcv_saddr = inet->saddr; + if (inet->inet_saddr == 0) + inet->inet_saddr = fl4->saddr; + inet->inet_rcv_saddr = inet->inet_saddr; - inet->dport = usin->sin_port; - inet->daddr = daddr; + inet->inet_dport = usin->sin_port; + inet->inet_daddr = daddr; inet_csk(sk)->icsk_ext_hdr_len = 0; - if (inet->opt != NULL) - inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; + if (inet_opt) + inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; /* * Socket identity is still unknown (sport may be zero). * However we set state to DCCP_REQUESTING and not releasing socket @@ -119,21 +108,21 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (err != 0) goto failure; - err = ip_route_newports(&rt, inet->sport, inet->dport, sk); - if (err != 0) + rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, + inet->inet_sport, inet->inet_dport, sk); + if (IS_ERR(rt)) { + err = PTR_ERR(rt); + rt = NULL; goto failure; - + } /* OK, now commit destination to socket. */ - sk_setup_caps(sk, &rt->u.dst); - - dp->dccps_gar = - dp->dccps_iss = secure_dccp_sequence_number(inet->saddr, - inet->daddr, - inet->sport, - usin->sin_port); - dccp_update_gss(sk, dp->dccps_iss); + sk_setup_caps(sk, &rt->dst); - inet->id = dp->dccps_iss ^ jiffies; + dp->dccps_iss = secure_dccp_sequence_number(inet->inet_saddr, + inet->inet_daddr, + inet->inet_sport, + inet->inet_dport); + inet->inet_id = dp->dccps_iss ^ jiffies; err = dccp_connect(sk); rt = NULL; @@ -148,7 +137,7 @@ failure: dccp_set_state(sk, DCCP_CLOSED); ip_rt_put(rt); sk->sk_route_caps = 0; - inet->dport = 0; + inet->inet_dport = 0; goto out; } @@ -172,17 +161,10 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk, if (sk->sk_state == DCCP_LISTEN) return; - /* We don't check in the destentry if pmtu discovery is forbidden - * on this route. We just assume that no packet_to_big packets - * are send back when pmtu discovery is not active. - * There is a small race when the user changes this flag in the - * route, but I think that's acceptable. - */ - if ((dst = __sk_dst_check(sk, 0)) == NULL) + dst = inet_csk_update_pmtu(sk, mtu); + if (!dst) return; - dst->ops->update_pmtu(dst, mtu); - /* Something is about to be wrong... Remember soft error * for the case, if this connection will not able to recover. */ @@ -192,11 +174,12 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk, mtu = dst_mtu(dst); if (inet->pmtudisc != IP_PMTUDISC_DONT && + ip_sk_accept_pmtu(sk) && inet_csk(sk)->icsk_pmtu_cookie > mtu) { dccp_sync_mss(sk, mtu); /* - * From: draft-ietf-dccp-spec-11.txt + * From RFC 4340, sec. 14.1: * * DCCP-Sync packets are the best choice for upward * probing, since DCCP-Sync probes do not risk application @@ -206,86 +189,12 @@ static inline void dccp_do_pmtu_discovery(struct sock *sk, } /* else let the usual retransmit timer handle it */ } -static void dccp_v4_ctl_send_ack(struct sk_buff *rxskb) -{ - int err; - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; - const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_ack_bits); - struct sk_buff *skb; - - if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL) - return; - - skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC); - if (skb == NULL) - return; - - /* Reserve space for headers. */ - skb_reserve(skb, MAX_DCCP_HEADER); - - skb->dst = dst_clone(rxskb->dst); - - skb->h.raw = skb_push(skb, dccp_hdr_ack_len); - dh = dccp_hdr(skb); - memset(dh, 0, dccp_hdr_ack_len); - - /* Build DCCP header and checksum it. */ - dh->dccph_type = DCCP_PKT_ACK; - dh->dccph_sport = rxdh->dccph_dport; - dh->dccph_dport = rxdh->dccph_sport; - dh->dccph_doff = dccp_hdr_ack_len / 4; - dh->dccph_x = 1; - - dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), - DCCP_SKB_CB(rxskb)->dccpd_seq); - - bh_lock_sock(dccp_ctl_socket->sk); - err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk, - rxskb->nh.iph->daddr, - rxskb->nh.iph->saddr, NULL); - bh_unlock_sock(dccp_ctl_socket->sk); - - if (err == NET_XMIT_CN || err == 0) { - DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); - DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); - } -} - -static void dccp_v4_reqsk_send_ack(struct sk_buff *skb, - struct request_sock *req) -{ - dccp_v4_ctl_send_ack(skb); -} - -static int dccp_v4_send_response(struct sock *sk, struct request_sock *req, - struct dst_entry *dst) +static void dccp_do_redirect(struct sk_buff *skb, struct sock *sk) { - int err = -1; - struct sk_buff *skb; - - /* First, grab a route. */ - - if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL) - goto out; - - skb = dccp_make_response(sk, dst, req); - if (skb != NULL) { - const struct inet_request_sock *ireq = inet_rsk(req); - - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); - err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, - ireq->rmt_addr, - ireq->opt); - if (err == NET_XMIT_CN) - err = 0; - } + struct dst_entry *dst = __sk_dst_check(sk, 0); -out: - dst_release(dst); - return err; + if (dst) + dst->ops->redirect(dst, sk, skb); } /* @@ -300,33 +209,36 @@ out: * check at all. A more general error queue to queue errors for later handling * is probably better. */ -void dccp_v4_err(struct sk_buff *skb, u32 info) +static void dccp_v4_err(struct sk_buff *skb, u32 info) { const struct iphdr *iph = (struct iphdr *)skb->data; - const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + - (iph->ihl << 2)); + const u8 offset = iph->ihl << 2; + const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset); struct dccp_sock *dp; struct inet_sock *inet; - const int type = skb->h.icmph->type; - const int code = skb->h.icmph->code; + const int type = icmp_hdr(skb)->type; + const int code = icmp_hdr(skb)->code; struct sock *sk; __u64 seq; int err; + struct net *net = dev_net(skb->dev); - if (skb->len < (iph->ihl << 2) + 8) { - ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); + if (skb->len < offset + sizeof(*dh) || + skb->len < offset + __dccp_basic_hdr_len(dh)) { + ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); return; } - sk = inet_lookup(&dccp_hashinfo, iph->daddr, dh->dccph_dport, - iph->saddr, dh->dccph_sport, inet_iif(skb)); + sk = inet_lookup(net, &dccp_hashinfo, + iph->daddr, dh->dccph_dport, + iph->saddr, dh->dccph_sport, inet_iif(skb)); if (sk == NULL) { - ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); + ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); return; } if (sk->sk_state == DCCP_TIME_WAIT) { - inet_twsk_put((struct inet_timewait_sock *)sk); + inet_twsk_put(inet_twsk(sk)); return; } @@ -335,20 +247,23 @@ void dccp_v4_err(struct sk_buff *skb, u32 info) * servers this needs to be solved differently. */ if (sock_owned_by_user(sk)) - NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); + NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); if (sk->sk_state == DCCP_CLOSED) goto out; dp = dccp_sk(sk); - seq = dccp_hdr_seq(skb); - if (sk->sk_state != DCCP_LISTEN && - !between48(seq, dp->dccps_swl, dp->dccps_swh)) { - NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS); + seq = dccp_hdr_seq(dh); + if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && + !between48(seq, dp->dccps_awl, dp->dccps_awh)) { + NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); goto out; } switch (type) { + case ICMP_REDIRECT: + dccp_do_redirect(skb, sk); + goto out; case ICMP_SOURCE_QUENCH: /* Just silently ignore these. */ goto out; @@ -388,10 +303,11 @@ void dccp_v4_err(struct sk_buff *skb, u32 info) * ICMPs are not backlogged, hence we cannot get an established * socket here. */ - BUG_TRAP(!req->sk); + WARN_ON(req->sk); - if (seq != dccp_rsk(req)->dreq_iss) { - NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); + if (!between48(seq, dccp_rsk(req)->dreq_iss, + dccp_rsk(req)->dreq_gss)) { + NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); goto out; } /* @@ -444,136 +360,33 @@ out: sock_put(sk); } -/* This routine computes an IPv4 DCCP checksum. */ -void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb) +static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, + __be32 src, __be32 dst) +{ + return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); +} + +void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb) { const struct inet_sock *inet = inet_sk(sk); struct dccp_hdr *dh = dccp_hdr(skb); - dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr); + dccp_csum_outgoing(skb); + dh->dccph_checksum = dccp_v4_csum_finish(skb, + inet->inet_saddr, + inet->inet_daddr); } EXPORT_SYMBOL_GPL(dccp_v4_send_check); -int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code) +static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) { - struct sk_buff *skb; - /* - * FIXME: what if rebuild_header fails? - * Should we be doing a rebuild_header here? - */ - int err = inet_sk_rebuild_header(sk); - - if (err != 0) - return err; - - skb = dccp_make_reset(sk, sk->sk_dst_cache, code); - if (skb != NULL) { - const struct inet_sock *inet = inet_sk(sk); - - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); - err = ip_build_and_send_pkt(skb, sk, - inet->saddr, inet->daddr, NULL); - if (err == NET_XMIT_CN) - err = 0; - } - - return err; -} - -static inline u64 dccp_v4_init_sequence(const struct sock *sk, - const struct sk_buff *skb) -{ - return secure_dccp_sequence_number(skb->nh.iph->daddr, - skb->nh.iph->saddr, + return secure_dccp_sequence_number(ip_hdr(skb)->daddr, + ip_hdr(skb)->saddr, dccp_hdr(skb)->dccph_dport, dccp_hdr(skb)->dccph_sport); } -int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) -{ - struct inet_request_sock *ireq; - struct dccp_sock dp; - struct request_sock *req; - struct dccp_request_sock *dreq; - const __u32 saddr = skb->nh.iph->saddr; - const __u32 daddr = skb->nh.iph->daddr; - const __u32 service = dccp_hdr_request(skb)->dccph_req_service; - struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); - __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY; - - /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ - if (((struct rtable *)skb->dst)->rt_flags & - (RTCF_BROADCAST | RTCF_MULTICAST)) { - reset_code = DCCP_RESET_CODE_NO_CONNECTION; - goto drop; - } - - if (dccp_bad_service_code(sk, service)) { - reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; - goto drop; - } - /* - * TW buckets are converted to open requests without - * limitations, they conserve resources and peer is - * evidently real one. - */ - if (inet_csk_reqsk_queue_is_full(sk)) - goto drop; - - /* - * Accept backlog is full. If we have already queued enough - * of warm entries in syn queue, drop request. It is better than - * clogging syn queue with openreqs with exponentially increasing - * timeout. - */ - if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) - goto drop; - - req = reqsk_alloc(sk->sk_prot->rsk_prot); - if (req == NULL) - goto drop; - - /* FIXME: process options */ - - dccp_openreq_init(req, &dp, skb); - - ireq = inet_rsk(req); - ireq->loc_addr = daddr; - ireq->rmt_addr = saddr; - req->rcv_wnd = 100; /* Fake, option parsing will get the - right value */ - ireq->opt = NULL; - - /* - * Step 3: Process LISTEN state - * - * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie - * - * In fact we defer setting S.GSR, S.SWL, S.SWH to - * dccp_create_openreq_child. - */ - dreq = dccp_rsk(req); - dreq->dreq_isr = dcb->dccpd_seq; - dreq->dreq_iss = dccp_v4_init_sequence(sk, skb); - dreq->dreq_service = service; - - if (dccp_v4_send_response(sk, req, NULL)) - goto drop_and_free; - - inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); - return 0; - -drop_and_free: - reqsk_free(req); -drop: - DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); - dcb->dccpd_reset_code = reset_code; - return -1; -} - -EXPORT_SYMBOL_GPL(dccp_v4_conn_request); - /* * The three way handshake has completed - we got a valid ACK or DATAACK - * now create the new socket. @@ -586,46 +399,50 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb, { struct inet_request_sock *ireq; struct inet_sock *newinet; - struct dccp_sock *newdp; struct sock *newsk; if (sk_acceptq_is_full(sk)) goto exit_overflow; - if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL) - goto exit; - newsk = dccp_create_openreq_child(sk, req, skb); if (newsk == NULL) - goto exit; + goto exit_nonewsk; - sk_setup_caps(newsk, dst); - - newdp = dccp_sk(newsk); newinet = inet_sk(newsk); ireq = inet_rsk(req); - newinet->daddr = ireq->rmt_addr; - newinet->rcv_saddr = ireq->loc_addr; - newinet->saddr = ireq->loc_addr; - newinet->opt = ireq->opt; + newinet->inet_daddr = ireq->ir_rmt_addr; + newinet->inet_rcv_saddr = ireq->ir_loc_addr; + newinet->inet_saddr = ireq->ir_loc_addr; + newinet->inet_opt = ireq->opt; ireq->opt = NULL; newinet->mc_index = inet_iif(skb); - newinet->mc_ttl = skb->nh.iph->ttl; - newinet->id = jiffies; + newinet->mc_ttl = ip_hdr(skb)->ttl; + newinet->inet_id = jiffies; + + if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) + goto put_and_exit; + + sk_setup_caps(newsk, dst); dccp_sync_mss(newsk, dst_mtu(dst)); - __inet_hash(&dccp_hashinfo, newsk, 0); - __inet_inherit_port(&dccp_hashinfo, sk, newsk); + if (__inet_inherit_port(sk, newsk) < 0) + goto put_and_exit; + __inet_hash_nolisten(newsk, NULL); return newsk; exit_overflow: - NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); -exit: - NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); +exit_nonewsk: dst_release(dst); +exit: + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); return NULL; +put_and_exit: + inet_csk_prepare_forced_close(newsk); + dccp_done(newsk); + goto exit; } EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); @@ -633,7 +450,7 @@ EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) { const struct dccp_hdr *dh = dccp_hdr(skb); - const struct iphdr *iph = skb->nh.iph; + const struct iphdr *iph = ip_hdr(skb); struct sock *nsk; struct request_sock **prev; /* Find possible connection requests. */ @@ -643,147 +460,111 @@ static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) if (req != NULL) return dccp_check_req(sk, skb, req, prev); - nsk = __inet_lookup_established(&dccp_hashinfo, - iph->saddr, dh->dccph_sport, - iph->daddr, ntohs(dh->dccph_dport), - inet_iif(skb)); + nsk = inet_lookup_established(sock_net(sk), &dccp_hashinfo, + iph->saddr, dh->dccph_sport, + iph->daddr, dh->dccph_dport, + inet_iif(skb)); if (nsk != NULL) { if (nsk->sk_state != DCCP_TIME_WAIT) { bh_lock_sock(nsk); return nsk; } - inet_twsk_put((struct inet_timewait_sock *)nsk); + inet_twsk_put(inet_twsk(nsk)); return NULL; } return sk; } -int dccp_v4_checksum(const struct sk_buff *skb, const u32 saddr, - const u32 daddr) +static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk, + struct sk_buff *skb) { - const struct dccp_hdr* dh = dccp_hdr(skb); - int checksum_len; - u32 tmp; - - if (dh->dccph_cscov == 0) - checksum_len = skb->len; - else { - checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32); - checksum_len = checksum_len < skb->len ? checksum_len : - skb->len; + struct rtable *rt; + const struct iphdr *iph = ip_hdr(skb); + struct flowi4 fl4 = { + .flowi4_oif = inet_iif(skb), + .daddr = iph->saddr, + .saddr = iph->daddr, + .flowi4_tos = RT_CONN_FLAGS(sk), + .flowi4_proto = sk->sk_protocol, + .fl4_sport = dccp_hdr(skb)->dccph_dport, + .fl4_dport = dccp_hdr(skb)->dccph_sport, + }; + + security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); + rt = ip_route_output_flow(net, &fl4, sk); + if (IS_ERR(rt)) { + IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); + return NULL; } - tmp = csum_partial((unsigned char *)dh, checksum_len, 0); - return csum_tcpudp_magic(saddr, daddr, checksum_len, - IPPROTO_DCCP, tmp); + return &rt->dst; } -static int dccp_v4_verify_checksum(struct sk_buff *skb, - const u32 saddr, const u32 daddr) +static int dccp_v4_send_response(struct sock *sk, struct request_sock *req) { - struct dccp_hdr *dh = dccp_hdr(skb); - int checksum_len; - u32 tmp; - - if (dh->dccph_cscov == 0) - checksum_len = skb->len; - else { - checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32); - checksum_len = checksum_len < skb->len ? checksum_len : - skb->len; - } - tmp = csum_partial((unsigned char *)dh, checksum_len, 0); - return csum_tcpudp_magic(saddr, daddr, checksum_len, - IPPROTO_DCCP, tmp) == 0 ? 0 : -1; -} + int err = -1; + struct sk_buff *skb; + struct dst_entry *dst; + struct flowi4 fl4; -static struct dst_entry* dccp_v4_route_skb(struct sock *sk, - struct sk_buff *skb) -{ - struct rtable *rt; - struct flowi fl = { .oif = ((struct rtable *)skb->dst)->rt_iif, - .nl_u = { .ip4_u = - { .daddr = skb->nh.iph->saddr, - .saddr = skb->nh.iph->daddr, - .tos = RT_CONN_FLAGS(sk) } }, - .proto = sk->sk_protocol, - .uli_u = { .ports = - { .sport = dccp_hdr(skb)->dccph_dport, - .dport = dccp_hdr(skb)->dccph_sport } - } - }; - - if (ip_route_output_flow(&rt, &fl, sk, 0)) { - IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); - return NULL; + dst = inet_csk_route_req(sk, &fl4, req); + if (dst == NULL) + goto out; + + skb = dccp_make_response(sk, dst, req); + if (skb != NULL) { + const struct inet_request_sock *ireq = inet_rsk(req); + struct dccp_hdr *dh = dccp_hdr(skb); + + dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->ir_loc_addr, + ireq->ir_rmt_addr); + err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, + ireq->ir_rmt_addr, + ireq->opt); + err = net_xmit_eval(err); } - return &rt->u.dst; +out: + dst_release(dst); + return err; } -static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) +static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) { int err; - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; - const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_reset); + const struct iphdr *rxiph; struct sk_buff *skb; struct dst_entry *dst; - u64 seqno; + struct net *net = dev_net(skb_dst(rxskb)->dev); + struct sock *ctl_sk = net->dccp.v4_ctl_sk; /* Never send a reset in response to a reset. */ - if (rxdh->dccph_type == DCCP_PKT_RESET) + if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) return; - if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL) + if (skb_rtable(rxskb)->rt_type != RTN_LOCAL) return; - dst = dccp_v4_route_skb(dccp_ctl_socket->sk, rxskb); + dst = dccp_v4_route_skb(net, ctl_sk, rxskb); if (dst == NULL) return; - skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC); + skb = dccp_ctl_make_reset(ctl_sk, rxskb); if (skb == NULL) goto out; - /* Reserve space for headers. */ - skb_reserve(skb, MAX_DCCP_HEADER); - skb->dst = dst_clone(dst); + rxiph = ip_hdr(rxskb); + dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, + rxiph->daddr); + skb_dst_set(skb, dst_clone(dst)); - skb->h.raw = skb_push(skb, dccp_hdr_reset_len); - dh = dccp_hdr(skb); - memset(dh, 0, dccp_hdr_reset_len); - - /* Build DCCP header and checksum it. */ - dh->dccph_type = DCCP_PKT_RESET; - dh->dccph_sport = rxdh->dccph_dport; - dh->dccph_dport = rxdh->dccph_sport; - dh->dccph_doff = dccp_hdr_reset_len / 4; - dh->dccph_x = 1; - dccp_hdr_reset(skb)->dccph_reset_code = - DCCP_SKB_CB(rxskb)->dccpd_reset_code; - - /* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */ - seqno = 0; - if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) - dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1); - - dccp_hdr_set_seq(dh, seqno); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), - DCCP_SKB_CB(rxskb)->dccpd_seq); - - dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr, - rxskb->nh.iph->daddr); - - bh_lock_sock(dccp_ctl_socket->sk); - err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk, - rxskb->nh.iph->daddr, - rxskb->nh.iph->saddr, NULL); - bh_unlock_sock(dccp_ctl_socket->sk); - - if (err == NET_XMIT_CN || err == 0) { + bh_lock_sock(ctl_sk); + err = ip_build_and_send_pkt(skb, ctl_sk, + rxiph->daddr, rxiph->saddr, NULL); + bh_unlock_sock(ctl_sk); + + if (net_xmit_eval(err) == 0) { DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); } @@ -791,6 +572,107 @@ out: dst_release(dst); } +static void dccp_v4_reqsk_destructor(struct request_sock *req) +{ + dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); + kfree(inet_rsk(req)->opt); +} + +void dccp_syn_ack_timeout(struct sock *sk, struct request_sock *req) +{ +} +EXPORT_SYMBOL(dccp_syn_ack_timeout); + +static struct request_sock_ops dccp_request_sock_ops __read_mostly = { + .family = PF_INET, + .obj_size = sizeof(struct dccp_request_sock), + .rtx_syn_ack = dccp_v4_send_response, + .send_ack = dccp_reqsk_send_ack, + .destructor = dccp_v4_reqsk_destructor, + .send_reset = dccp_v4_ctl_send_reset, + .syn_ack_timeout = dccp_syn_ack_timeout, +}; + +int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) +{ + struct inet_request_sock *ireq; + struct request_sock *req; + struct dccp_request_sock *dreq; + const __be32 service = dccp_hdr_request(skb)->dccph_req_service; + struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); + + /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ + if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) + return 0; /* discard, don't send a reset here */ + + if (dccp_bad_service_code(sk, service)) { + dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; + goto drop; + } + /* + * TW buckets are converted to open requests without + * limitations, they conserve resources and peer is + * evidently real one. + */ + dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; + if (inet_csk_reqsk_queue_is_full(sk)) + goto drop; + + /* + * Accept backlog is full. If we have already queued enough + * of warm entries in syn queue, drop request. It is better than + * clogging syn queue with openreqs with exponentially increasing + * timeout. + */ + if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) + goto drop; + + req = inet_reqsk_alloc(&dccp_request_sock_ops); + if (req == NULL) + goto drop; + + if (dccp_reqsk_init(req, dccp_sk(sk), skb)) + goto drop_and_free; + + dreq = dccp_rsk(req); + if (dccp_parse_options(sk, dreq, skb)) + goto drop_and_free; + + if (security_inet_conn_request(sk, skb, req)) + goto drop_and_free; + + ireq = inet_rsk(req); + ireq->ir_loc_addr = ip_hdr(skb)->daddr; + ireq->ir_rmt_addr = ip_hdr(skb)->saddr; + + /* + * Step 3: Process LISTEN state + * + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie + * + * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). + */ + dreq->dreq_isr = dcb->dccpd_seq; + dreq->dreq_gsr = dreq->dreq_isr; + dreq->dreq_iss = dccp_v4_init_sequence(skb); + dreq->dreq_gss = dreq->dreq_iss; + dreq->dreq_service = service; + + if (dccp_v4_send_response(sk, req)) + goto drop_and_free; + + inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); + return 0; + +drop_and_free: + reqsk_free(req); +drop: + DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); + return -1; +} + +EXPORT_SYMBOL_GPL(dccp_v4_conn_request); + int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) { struct dccp_hdr *dh = dccp_hdr(skb); @@ -803,24 +685,23 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) /* * Step 3: Process LISTEN state - * If S.state == LISTEN, - * If P.type == Request or P contains a valid Init Cookie - * option, - * * Must scan the packet's options to check for an Init - * Cookie. Only the Init Cookie is processed here, - * however; other options are processed in Step 8. This - * scan need only be performed if the endpoint uses Init - * Cookies * - * * Generate a new socket and switch to that socket * - * Set S := new socket for this port pair - * S.state = RESPOND - * Choose S.ISS (initial seqno) or set from Init Cookie - * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie - * Continue with S.state == RESPOND - * * A Response packet will be generated in Step 11 * - * Otherwise, - * Generate Reset(No Connection) unless P.type == Reset - * Drop packet and return + * If P.type == Request or P contains a valid Init Cookie option, + * (* Must scan the packet's options to check for Init + * Cookies. Only Init Cookies are processed here, + * however; other options are processed in Step 8. This + * scan need only be performed if the endpoint uses Init + * Cookies *) + * (* Generate a new socket and switch to that socket *) + * Set S := new socket for this port pair + * S.state = RESPOND + * Choose S.ISS (initial seqno) or set from Init Cookies + * Initialize S.GAR := S.ISS + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies + * Continue with S.state == RESPOND + * (* A Response packet will be generated in Step 11 *) + * Otherwise, + * Generate Reset(No Connection) unless P.type == Reset + * Drop packet and return * * NOTE: the check for the packet types is done in * dccp_rcv_state_process @@ -843,7 +724,7 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) return 0; reset: - dccp_v4_ctl_send_reset(skb); + dccp_v4_ctl_send_reset(sk, skb); discard: kfree_skb(skb); return 0; @@ -851,95 +732,108 @@ discard: EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); +/** + * dccp_invalid_packet - check for malformed packets + * Implements RFC 4340, 8.5: Step 1: Check header basics + * Packets that fail these checks are ignored and do not receive Resets. + */ int dccp_invalid_packet(struct sk_buff *skb) { const struct dccp_hdr *dh; + unsigned int cscov; if (skb->pkt_type != PACKET_HOST) return 1; + /* If the packet is shorter than 12 bytes, drop packet and return */ if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n"); + DCCP_WARN("pskb_may_pull failed\n"); return 1; } dh = dccp_hdr(skb); - /* If the packet type is not understood, drop packet and return */ + /* If P.type is not understood, drop packet and return */ if (dh->dccph_type >= DCCP_PKT_INVALID) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n"); + DCCP_WARN("invalid packet type\n"); return 1; } /* - * If P.Data Offset is too small for packet type, or too large for - * packet, drop packet and return + * If P.Data Offset is too small for packet type, drop packet and return */ if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) " - "too small 1\n", - dh->dccph_doff); + DCCP_WARN("P.Data Offset(%u) too small\n", dh->dccph_doff); return 1; } - + /* + * If P.Data Offset is too too large for packet, drop packet and return + */ if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) " - "too small 2\n", - dh->dccph_doff); + DCCP_WARN("P.Data Offset(%u) too large\n", dh->dccph_doff); return 1; } - dh = dccp_hdr(skb); - /* * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet * has short sequence numbers), drop packet and return */ - if (dh->dccph_x == 0 && - dh->dccph_type != DCCP_PKT_DATA && - dh->dccph_type != DCCP_PKT_ACK && - dh->dccph_type != DCCP_PKT_DATAACK) { - LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack " - "nor DataAck and P.X == 0\n", - dccp_packet_name(dh->dccph_type)); + if ((dh->dccph_type < DCCP_PKT_DATA || + dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { + DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", + dccp_packet_name(dh->dccph_type)); return 1; } + /* + * If P.CsCov is too large for the packet size, drop packet and return. + * This must come _before_ checksumming (not as RFC 4340 suggests). + */ + cscov = dccp_csum_coverage(skb); + if (cscov > skb->len) { + DCCP_WARN("P.CsCov %u exceeds packet length %d\n", + dh->dccph_cscov, skb->len); + return 1; + } + + /* If header checksum is incorrect, drop packet and return. + * (This step is completed in the AF-dependent functions.) */ + skb->csum = skb_checksum(skb, 0, cscov, 0); + return 0; } EXPORT_SYMBOL_GPL(dccp_invalid_packet); /* this is called when real data arrives */ -int dccp_v4_rcv(struct sk_buff *skb) +static int dccp_v4_rcv(struct sk_buff *skb) { const struct dccp_hdr *dh; + const struct iphdr *iph; struct sock *sk; + int min_cov; - /* Step 1: Check header basics: */ + /* Step 1: Check header basics */ if (dccp_invalid_packet(skb)) goto discard_it; - /* If the header checksum is incorrect, drop packet and return */ - if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr, - skb->nh.iph->daddr) < 0) { - LIMIT_NETDEBUG(KERN_WARNING "%s: incorrect header checksum\n", - __FUNCTION__); + iph = ip_hdr(skb); + /* Step 1: If header checksum is incorrect, drop packet and return */ + if (dccp_v4_csum_finish(skb, iph->saddr, iph->daddr)) { + DCCP_WARN("dropped packet with invalid checksum\n"); goto discard_it; } dh = dccp_hdr(skb); - DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb); + DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; - dccp_pr_debug("%8.8s " - "src=%u.%u.%u.%u@%-5d " - "dst=%u.%u.%u.%u@%-5d seq=%llu", + dccp_pr_debug("%8.8s src=%pI4@%-5d dst=%pI4@%-5d seq=%llu", dccp_packet_name(dh->dccph_type), - NIPQUAD(skb->nh.iph->saddr), ntohs(dh->dccph_sport), - NIPQUAD(skb->nh.iph->daddr), ntohs(dh->dccph_dport), + &iph->saddr, ntohs(dh->dccph_sport), + &iph->daddr, ntohs(dh->dccph_dport), (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); if (dccp_packet_without_ack(skb)) { @@ -947,23 +841,17 @@ int dccp_v4_rcv(struct sk_buff *skb) dccp_pr_debug_cat("\n"); } else { DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); - dccp_pr_debug_cat(", ack=%llu\n", - (unsigned long long) + dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq); } /* Step 2: - * Look up flow ID in table and get corresponding socket */ - sk = __inet_lookup(&dccp_hashinfo, - skb->nh.iph->saddr, dh->dccph_sport, - skb->nh.iph->daddr, ntohs(dh->dccph_dport), - inet_iif(skb)); - - /* + * Look up flow ID in table and get corresponding socket */ + sk = __inet_lookup_skb(&dccp_hashinfo, skb, + dh->dccph_sport, dh->dccph_dport); + /* * Step 2: - * If no socket ... - * Generate Reset(No Connection) unless P.type == Reset - * Drop packet and return + * If no socket ... */ if (sk == NULL) { dccp_pr_debug("failed to look up flow ID in table and " @@ -971,177 +859,100 @@ int dccp_v4_rcv(struct sk_buff *skb) goto no_dccp_socket; } - /* + /* * Step 2: - * ... or S.state == TIMEWAIT, + * ... or S.state == TIMEWAIT, * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ - if (sk->sk_state == DCCP_TIME_WAIT) { - dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: " - "do_time_wait\n"); - goto do_time_wait; + dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); + inet_twsk_put(inet_twsk(sk)); + goto no_dccp_socket; + } + + /* + * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage + * o if MinCsCov = 0, only packets with CsCov = 0 are accepted + * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov + */ + min_cov = dccp_sk(sk)->dccps_pcrlen; + if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { + dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", + dh->dccph_cscov, min_cov); + /* FIXME: "Such packets SHOULD be reported using Data Dropped + * options (Section 11.7) with Drop Code 0, Protocol + * Constraints." */ + goto discard_and_relse; } if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) goto discard_and_relse; nf_reset(skb); - return sk_receive_skb(sk, skb); + return sk_receive_skb(sk, skb, 1); no_dccp_socket: if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto discard_it; /* * Step 2: + * If no socket ... * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ if (dh->dccph_type != DCCP_PKT_RESET) { DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; - dccp_v4_ctl_send_reset(skb); + dccp_v4_ctl_send_reset(sk, skb); } discard_it: - /* Discard frame. */ kfree_skb(skb); return 0; discard_and_relse: sock_put(sk); goto discard_it; - -do_time_wait: - inet_twsk_put((struct inet_timewait_sock *)sk); - goto no_dccp_socket; } -struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { - .queue_xmit = ip_queue_xmit, - .send_check = dccp_v4_send_check, - .rebuild_header = inet_sk_rebuild_header, - .conn_request = dccp_v4_conn_request, - .syn_recv_sock = dccp_v4_request_recv_sock, - .net_header_len = sizeof(struct iphdr), - .setsockopt = ip_setsockopt, - .getsockopt = ip_getsockopt, - .addr2sockaddr = inet_csk_addr2sockaddr, - .sockaddr_len = sizeof(struct sockaddr_in), +static const struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { + .queue_xmit = ip_queue_xmit, + .send_check = dccp_v4_send_check, + .rebuild_header = inet_sk_rebuild_header, + .conn_request = dccp_v4_conn_request, + .syn_recv_sock = dccp_v4_request_recv_sock, + .net_header_len = sizeof(struct iphdr), + .setsockopt = ip_setsockopt, + .getsockopt = ip_getsockopt, + .addr2sockaddr = inet_csk_addr2sockaddr, + .sockaddr_len = sizeof(struct sockaddr_in), + .bind_conflict = inet_csk_bind_conflict, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_ip_setsockopt, + .compat_getsockopt = compat_ip_getsockopt, +#endif }; -int dccp_v4_init_sock(struct sock *sk) +static int dccp_v4_init_sock(struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct inet_connection_sock *icsk = inet_csk(sk); - static int dccp_ctl_socket_init = 1; - - dccp_options_init(&dp->dccps_options); - do_gettimeofday(&dp->dccps_epoch); + static __u8 dccp_v4_ctl_sock_initialized; + int err = dccp_init_sock(sk, dccp_v4_ctl_sock_initialized); - if (dp->dccps_options.dccpo_send_ack_vector) { - dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN, - GFP_KERNEL); - if (dp->dccps_hc_rx_ackvec == NULL) - return -ENOMEM; + if (err == 0) { + if (unlikely(!dccp_v4_ctl_sock_initialized)) + dccp_v4_ctl_sock_initialized = 1; + inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; } - /* - * FIXME: We're hardcoding the CCID, and doing this at this point makes - * the listening (master) sock get CCID control blocks, which is not - * necessary, but for now, to not mess with the test userspace apps, - * lets leave it here, later the real solution is to do this in a - * setsockopt(CCIDs-I-want/accept). -acme - */ - if (likely(!dccp_ctl_socket_init)) { - dp->dccps_hc_rx_ccid = ccid_init(dp->dccps_options.dccpo_rx_ccid, - sk); - dp->dccps_hc_tx_ccid = ccid_init(dp->dccps_options.dccpo_tx_ccid, - sk); - if (dp->dccps_hc_rx_ccid == NULL || - dp->dccps_hc_tx_ccid == NULL) { - ccid_exit(dp->dccps_hc_rx_ccid, sk); - ccid_exit(dp->dccps_hc_tx_ccid, sk); - if (dp->dccps_options.dccpo_send_ack_vector) { - dccp_ackvec_free(dp->dccps_hc_rx_ackvec); - dp->dccps_hc_rx_ackvec = NULL; - } - dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL; - return -ENOMEM; - } - } else - dccp_ctl_socket_init = 0; - - dccp_init_xmit_timers(sk); - icsk->icsk_rto = DCCP_TIMEOUT_INIT; - sk->sk_state = DCCP_CLOSED; - sk->sk_write_space = dccp_write_space; - icsk->icsk_af_ops = &dccp_ipv4_af_ops; - icsk->icsk_sync_mss = dccp_sync_mss; - dp->dccps_mss_cache = 536; - dp->dccps_role = DCCP_ROLE_UNDEFINED; - dp->dccps_service = DCCP_SERVICE_INVALID_VALUE; - - return 0; -} - -EXPORT_SYMBOL_GPL(dccp_v4_init_sock); - -int dccp_v4_destroy_sock(struct sock *sk) -{ - struct dccp_sock *dp = dccp_sk(sk); - - /* - * DCCP doesn't use sk_write_queue, just sk_send_head - * for retransmissions - */ - if (sk->sk_send_head != NULL) { - kfree_skb(sk->sk_send_head); - sk->sk_send_head = NULL; - } - - /* Clean up a referenced DCCP bind bucket. */ - if (inet_csk(sk)->icsk_bind_hash != NULL) - inet_put_port(&dccp_hashinfo, sk); - - kfree(dp->dccps_service_list); - dp->dccps_service_list = NULL; - - ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk); - ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk); - if (dp->dccps_options.dccpo_send_ack_vector) { - dccp_ackvec_free(dp->dccps_hc_rx_ackvec); - dp->dccps_hc_rx_ackvec = NULL; - } - ccid_exit(dp->dccps_hc_rx_ccid, sk); - ccid_exit(dp->dccps_hc_tx_ccid, sk); - dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL; - - return 0; -} - -EXPORT_SYMBOL_GPL(dccp_v4_destroy_sock); - -static void dccp_v4_reqsk_destructor(struct request_sock *req) -{ - kfree(inet_rsk(req)->opt); + return err; } -static struct request_sock_ops dccp_request_sock_ops = { - .family = PF_INET, - .obj_size = sizeof(struct dccp_request_sock), - .rtx_syn_ack = dccp_v4_send_response, - .send_ack = dccp_v4_reqsk_send_ack, - .destructor = dccp_v4_reqsk_destructor, - .send_reset = dccp_v4_ctl_send_reset, -}; - static struct timewait_sock_ops dccp_timewait_sock_ops = { .twsk_obj_size = sizeof(struct inet_timewait_sock), }; -struct proto dccp_prot = { +static struct proto dccp_v4_prot = { .name = "DCCP", .owner = THIS_MODULE, .close = dccp_close, @@ -1154,17 +965,131 @@ struct proto dccp_prot = { .sendmsg = dccp_sendmsg, .recvmsg = dccp_recvmsg, .backlog_rcv = dccp_v4_do_rcv, - .hash = dccp_v4_hash, - .unhash = dccp_unhash, + .hash = inet_hash, + .unhash = inet_unhash, .accept = inet_csk_accept, - .get_port = dccp_v4_get_port, + .get_port = inet_csk_get_port, .shutdown = dccp_shutdown, - .destroy = dccp_v4_destroy_sock, + .destroy = dccp_destroy_sock, .orphan_count = &dccp_orphan_count, .max_header = MAX_DCCP_HEADER, .obj_size = sizeof(struct dccp_sock), + .slab_flags = SLAB_DESTROY_BY_RCU, .rsk_prot = &dccp_request_sock_ops, .twsk_prot = &dccp_timewait_sock_ops, + .h.hashinfo = &dccp_hashinfo, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_dccp_setsockopt, + .compat_getsockopt = compat_dccp_getsockopt, +#endif +}; + +static const struct net_protocol dccp_v4_protocol = { + .handler = dccp_v4_rcv, + .err_handler = dccp_v4_err, + .no_policy = 1, + .netns_ok = 1, + .icmp_strict_tag_validation = 1, +}; + +static const struct proto_ops inet_dccp_ops = { + .family = PF_INET, + .owner = THIS_MODULE, + .release = inet_release, + .bind = inet_bind, + .connect = inet_stream_connect, + .socketpair = sock_no_socketpair, + .accept = inet_accept, + .getname = inet_getname, + /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ + .poll = dccp_poll, + .ioctl = inet_ioctl, + /* FIXME: work on inet_listen to rename it to sock_common_listen */ + .listen = inet_dccp_listen, + .shutdown = inet_shutdown, + .setsockopt = sock_common_setsockopt, + .getsockopt = sock_common_getsockopt, + .sendmsg = inet_sendmsg, + .recvmsg = sock_common_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_sock_common_setsockopt, + .compat_getsockopt = compat_sock_common_getsockopt, +#endif +}; + +static struct inet_protosw dccp_v4_protosw = { + .type = SOCK_DCCP, + .protocol = IPPROTO_DCCP, + .prot = &dccp_v4_prot, + .ops = &inet_dccp_ops, + .flags = INET_PROTOSW_ICSK, +}; + +static int __net_init dccp_v4_init_net(struct net *net) +{ + if (dccp_hashinfo.bhash == NULL) + return -ESOCKTNOSUPPORT; + + return inet_ctl_sock_create(&net->dccp.v4_ctl_sk, PF_INET, + SOCK_DCCP, IPPROTO_DCCP, net); +} + +static void __net_exit dccp_v4_exit_net(struct net *net) +{ + inet_ctl_sock_destroy(net->dccp.v4_ctl_sk); +} + +static struct pernet_operations dccp_v4_ops = { + .init = dccp_v4_init_net, + .exit = dccp_v4_exit_net, }; -EXPORT_SYMBOL_GPL(dccp_prot); +static int __init dccp_v4_init(void) +{ + int err = proto_register(&dccp_v4_prot, 1); + + if (err != 0) + goto out; + + err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP); + if (err != 0) + goto out_proto_unregister; + + inet_register_protosw(&dccp_v4_protosw); + + err = register_pernet_subsys(&dccp_v4_ops); + if (err) + goto out_destroy_ctl_sock; +out: + return err; +out_destroy_ctl_sock: + inet_unregister_protosw(&dccp_v4_protosw); + inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); +out_proto_unregister: + proto_unregister(&dccp_v4_prot); + goto out; +} + +static void __exit dccp_v4_exit(void) +{ + unregister_pernet_subsys(&dccp_v4_ops); + inet_unregister_protosw(&dccp_v4_protosw); + inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); + proto_unregister(&dccp_v4_prot); +} + +module_init(dccp_v4_init); +module_exit(dccp_v4_exit); + +/* + * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) + * values directly, Also cover the case where the protocol is not specified, + * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP + */ +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); +MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index df074259f9c..4db3c2a1679 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -1,6 +1,6 @@ /* * DCCP over IPv6 - * Linux INET6 implementation + * Linux INET6 implementation * * Based on net/dccp6/ipv6.c * @@ -12,9 +12,9 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/module.h> #include <linux/random.h> +#include <linux/slab.h> #include <linux/xfrm.h> #include <net/addrconf.h> @@ -29,322 +29,137 @@ #include <net/transp_v6.h> #include <net/ip6_checksum.h> #include <net/xfrm.h> +#include <net/secure_seq.h> #include "dccp.h" #include "ipv6.h" +#include "feat.h" -static void dccp_v6_ctl_send_reset(struct sk_buff *skb); -static void dccp_v6_reqsk_send_ack(struct sk_buff *skb, - struct request_sock *req); -static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb); +/* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */ -static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); - -static struct inet_connection_sock_af_ops dccp_ipv6_mapped; -static struct inet_connection_sock_af_ops dccp_ipv6_af_ops; - -static int dccp_v6_get_port(struct sock *sk, unsigned short snum) -{ - return inet_csk_get_port(&dccp_hashinfo, sk, snum, - inet6_csk_bind_conflict); -} +static const struct inet_connection_sock_af_ops dccp_ipv6_mapped; +static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops; static void dccp_v6_hash(struct sock *sk) { if (sk->sk_state != DCCP_CLOSED) { if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) { - dccp_prot.hash(sk); + inet_hash(sk); return; } local_bh_disable(); - __inet6_hash(&dccp_hashinfo, sk); + __inet6_hash(sk, NULL); local_bh_enable(); } } -static inline u16 dccp_v6_check(struct dccp_hdr *dh, int len, - struct in6_addr *saddr, - struct in6_addr *daddr, - unsigned long base) +/* add pseudo-header to DCCP checksum stored in skb->csum */ +static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb, + const struct in6_addr *saddr, + const struct in6_addr *daddr) { - return csum_ipv6_magic(saddr, daddr, len, IPPROTO_DCCP, base); + return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum); } -static __u32 dccp_v6_init_sequence(struct sock *sk, struct sk_buff *skb) +static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb) { - const struct dccp_hdr *dh = dccp_hdr(skb); + struct ipv6_pinfo *np = inet6_sk(sk); + struct dccp_hdr *dh = dccp_hdr(skb); - if (skb->protocol == htons(ETH_P_IPV6)) - return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32, - skb->nh.ipv6h->saddr.s6_addr32, - dh->dccph_dport, - dh->dccph_sport); - else - return secure_dccp_sequence_number(skb->nh.iph->daddr, - skb->nh.iph->saddr, - dh->dccph_dport, - dh->dccph_sport); + dccp_csum_outgoing(skb); + dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr); } -static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, - int addr_len) +static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb) { - struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; - struct inet_connection_sock *icsk = inet_csk(sk); - struct inet_sock *inet = inet_sk(sk); - struct ipv6_pinfo *np = inet6_sk(sk); - struct dccp_sock *dp = dccp_sk(sk); - struct in6_addr *saddr = NULL, *final_p = NULL, final; - struct flowi fl; - struct dst_entry *dst; - int addr_type; - int err; - - dp->dccps_role = DCCP_ROLE_CLIENT; - - if (addr_len < SIN6_LEN_RFC2133) - return -EINVAL; - - if (usin->sin6_family != AF_INET6) - return -EAFNOSUPPORT; - - memset(&fl, 0, sizeof(fl)); - - if (np->sndflow) { - fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; - IP6_ECN_flow_init(fl.fl6_flowlabel); - if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) { - struct ip6_flowlabel *flowlabel; - flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); - if (flowlabel == NULL) - return -EINVAL; - ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst); - fl6_sock_release(flowlabel); - } - } - - /* - * connect() to INADDR_ANY means loopback (BSD'ism). - */ - - if (ipv6_addr_any(&usin->sin6_addr)) - usin->sin6_addr.s6_addr[15] = 0x1; - - addr_type = ipv6_addr_type(&usin->sin6_addr); - - if(addr_type & IPV6_ADDR_MULTICAST) - return -ENETUNREACH; - - if (addr_type & IPV6_ADDR_LINKLOCAL) { - if (addr_len >= sizeof(struct sockaddr_in6) && - usin->sin6_scope_id) { - /* If interface is set while binding, indices - * must coincide. - */ - if (sk->sk_bound_dev_if && - sk->sk_bound_dev_if != usin->sin6_scope_id) - return -EINVAL; - - sk->sk_bound_dev_if = usin->sin6_scope_id; - } - - /* Connect to link-local address requires an interface */ - if (!sk->sk_bound_dev_if) - return -EINVAL; - } - - ipv6_addr_copy(&np->daddr, &usin->sin6_addr); - np->flow_label = fl.fl6_flowlabel; - - /* - * DCCP over IPv4 - */ - - if (addr_type == IPV6_ADDR_MAPPED) { - u32 exthdrlen = icsk->icsk_ext_hdr_len; - struct sockaddr_in sin; - - SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); - - if (__ipv6_only_sock(sk)) - return -ENETUNREACH; - - sin.sin_family = AF_INET; - sin.sin_port = usin->sin6_port; - sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; - - icsk->icsk_af_ops = &dccp_ipv6_mapped; - sk->sk_backlog_rcv = dccp_v4_do_rcv; - - err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); - - if (err) { - icsk->icsk_ext_hdr_len = exthdrlen; - icsk->icsk_af_ops = &dccp_ipv6_af_ops; - sk->sk_backlog_rcv = dccp_v6_do_rcv; - goto failure; - } else { - ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF), - inet->saddr); - ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF), - inet->rcv_saddr); - } - - return err; - } - - if (!ipv6_addr_any(&np->rcv_saddr)) - saddr = &np->rcv_saddr; - - fl.proto = IPPROTO_DCCP; - ipv6_addr_copy(&fl.fl6_dst, &np->daddr); - ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr); - fl.oif = sk->sk_bound_dev_if; - fl.fl_ip_dport = usin->sin6_port; - fl.fl_ip_sport = inet->sport; - - if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } - - err = ip6_dst_lookup(sk, &dst, &fl); - if (err) - goto failure; - if (final_p) - ipv6_addr_copy(&fl.fl6_dst, final_p); - - if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) - goto failure; - - if (saddr == NULL) { - saddr = &fl.fl6_src; - ipv6_addr_copy(&np->rcv_saddr, saddr); - } - - /* set the source address */ - ipv6_addr_copy(&np->saddr, saddr); - inet->rcv_saddr = LOOPBACK4_IPV6; - - ip6_dst_store(sk, dst, NULL); + return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32, + ipv6_hdr(skb)->saddr.s6_addr32, + dccp_hdr(skb)->dccph_dport, + dccp_hdr(skb)->dccph_sport ); - icsk->icsk_ext_hdr_len = 0; - if (np->opt) - icsk->icsk_ext_hdr_len = (np->opt->opt_flen + - np->opt->opt_nflen); - - inet->dport = usin->sin6_port; - - dccp_set_state(sk, DCCP_REQUESTING); - err = inet6_hash_connect(&dccp_death_row, sk); - if (err) - goto late_failure; - /* FIXME */ -#if 0 - dp->dccps_gar = secure_dccp_v6_sequence_number(np->saddr.s6_addr32, - np->daddr.s6_addr32, - inet->sport, - inet->dport); -#endif - err = dccp_connect(sk); - if (err) - goto late_failure; - - return 0; - -late_failure: - dccp_set_state(sk, DCCP_CLOSED); - __sk_dst_reset(sk); -failure: - inet->dport = 0; - sk->sk_route_caps = 0; - return err; } static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, - int type, int code, int offset, __u32 info) + u8 type, u8 code, int offset, __be32 info) { - struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data; + const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset); + struct dccp_sock *dp; struct ipv6_pinfo *np; struct sock *sk; int err; __u64 seq; + struct net *net = dev_net(skb->dev); + + if (skb->len < offset + sizeof(*dh) || + skb->len < offset + __dccp_basic_hdr_len(dh)) { + ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), + ICMP6_MIB_INERRORS); + return; + } - sk = inet6_lookup(&dccp_hashinfo, &hdr->daddr, dh->dccph_dport, - &hdr->saddr, dh->dccph_sport, skb->dev->ifindex); + sk = inet6_lookup(net, &dccp_hashinfo, + &hdr->daddr, dh->dccph_dport, + &hdr->saddr, dh->dccph_sport, inet6_iif(skb)); if (sk == NULL) { - ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); + ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), + ICMP6_MIB_INERRORS); return; } if (sk->sk_state == DCCP_TIME_WAIT) { - inet_twsk_put((struct inet_timewait_sock *)sk); + inet_twsk_put(inet_twsk(sk)); return; } bh_lock_sock(sk); if (sock_owned_by_user(sk)) - NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); + NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); if (sk->sk_state == DCCP_CLOSED) goto out; + dp = dccp_sk(sk); + seq = dccp_hdr_seq(dh); + if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && + !between48(seq, dp->dccps_awl, dp->dccps_awh)) { + NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); + goto out; + } + np = inet6_sk(sk); + if (type == NDISC_REDIRECT) { + struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie); + + if (dst) + dst->ops->redirect(dst, sk, skb); + goto out; + } + if (type == ICMPV6_PKT_TOOBIG) { struct dst_entry *dst = NULL; + if (!ip6_sk_accept_pmtu(sk)) + goto out; + if (sock_owned_by_user(sk)) goto out; if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED)) goto out; - /* icmp should have updated the destination cache entry */ - dst = __sk_dst_check(sk, np->dst_cookie); - - if (dst == NULL) { - struct inet_sock *inet = inet_sk(sk); - struct flowi fl; - - /* BUGGG_FUTURE: Again, it is not clear how - to handle rthdr case. Ignore this complexity - for now. - */ - memset(&fl, 0, sizeof(fl)); - fl.proto = IPPROTO_DCCP; - ipv6_addr_copy(&fl.fl6_dst, &np->daddr); - ipv6_addr_copy(&fl.fl6_src, &np->saddr); - fl.oif = sk->sk_bound_dev_if; - fl.fl_ip_dport = inet->dport; - fl.fl_ip_sport = inet->sport; - - if ((err = ip6_dst_lookup(sk, &dst, &fl))) { - sk->sk_err_soft = -err; - goto out; - } - - if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { - sk->sk_err_soft = -err; - goto out; - } - - } else - dst_hold(dst); + dst = inet6_csk_update_pmtu(sk, ntohl(info)); + if (!dst) + goto out; - if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) { + if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) dccp_sync_mss(sk, dst_mtu(dst)); - } /* else let the usual retransmit timer handle it */ - dst_release(dst); goto out; } icmpv6_err_convert(type, code, &err); - seq = DCCP_SKB_CB(skb)->dccpd_seq; /* Might be for an request_sock */ switch (sk->sk_state) { struct request_sock *req, **prev; @@ -355,16 +170,18 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, req = inet6_csk_search_req(sk, &prev, dh->dccph_dport, &hdr->daddr, &hdr->saddr, inet6_iif(skb)); - if (!req) + if (req == NULL) goto out; - /* ICMPs are not backlogged, hence we cannot get - * an established socket here. + /* + * ICMPs are not backlogged, hence we cannot get an established + * socket here. */ - BUG_TRAP(req->sk == NULL); + WARN_ON(req->sk != NULL); - if (seq != dccp_rsk(req)->dreq_iss) { - NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); + if (!between48(seq, dccp_rsk(req)->dreq_iss, + dccp_rsk(req)->dreq_gss)) { + NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); goto out; } @@ -373,7 +190,7 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, case DCCP_REQUESTING: case DCCP_RESPOND: /* Cannot happen. - It can, it SYNs are crossed. --ANK */ + It can, it SYNs are crossed. --ANK */ if (!sock_owned_by_user(sk)) { DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); sk->sk_err = err; @@ -382,7 +199,6 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, * (see connect in sock.c) */ sk->sk_error_report(sk); - dccp_done(sk); } else sk->sk_err_soft = err; @@ -401,246 +217,119 @@ out: } -static int dccp_v6_send_response(struct sock *sk, struct request_sock *req, - struct dst_entry *dst) +static int dccp_v6_send_response(struct sock *sk, struct request_sock *req) { - struct inet6_request_sock *ireq6 = inet6_rsk(req); + struct inet_request_sock *ireq = inet_rsk(req); struct ipv6_pinfo *np = inet6_sk(sk); struct sk_buff *skb; - struct ipv6_txoptions *opt = NULL; - struct in6_addr *final_p = NULL, final; - struct flowi fl; + struct in6_addr *final_p, final; + struct flowi6 fl6; int err = -1; + struct dst_entry *dst; - memset(&fl, 0, sizeof(fl)); - fl.proto = IPPROTO_DCCP; - ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); - ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); - fl.fl6_flowlabel = 0; - fl.oif = ireq6->iif; - fl.fl_ip_dport = inet_rsk(req)->rmt_port; - fl.fl_ip_sport = inet_sk(sk)->sport; + memset(&fl6, 0, sizeof(fl6)); + fl6.flowi6_proto = IPPROTO_DCCP; + fl6.daddr = ireq->ir_v6_rmt_addr; + fl6.saddr = ireq->ir_v6_loc_addr; + fl6.flowlabel = 0; + fl6.flowi6_oif = ireq->ir_iif; + fl6.fl6_dport = ireq->ir_rmt_port; + fl6.fl6_sport = htons(ireq->ir_num); + security_req_classify_flow(req, flowi6_to_flowi(&fl6)); - if (dst == NULL) { - opt = np->opt; - if (opt == NULL && - np->rxopt.bits.osrcrt == 2 && - ireq6->pktopts) { - struct sk_buff *pktopts = ireq6->pktopts; - struct inet6_skb_parm *rxopt = IP6CB(pktopts); - if (rxopt->srcrt) - opt = ipv6_invert_rthdr(sk, - (struct ipv6_rt_hdr *)(pktopts->nh.raw + - rxopt->srcrt)); - } - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = fl6_update_dst(&fl6, np->opt, &final); - err = ip6_dst_lookup(sk, &dst, &fl); - if (err) - goto done; - if (final_p) - ipv6_addr_copy(&fl.fl6_dst, final_p); - if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) - goto done; + dst = ip6_dst_lookup_flow(sk, &fl6, final_p); + if (IS_ERR(dst)) { + err = PTR_ERR(dst); + dst = NULL; + goto done; } skb = dccp_make_response(sk, dst, req); if (skb != NULL) { struct dccp_hdr *dh = dccp_hdr(skb); - dh->dccph_checksum = dccp_v6_check(dh, skb->len, - &ireq6->loc_addr, - &ireq6->rmt_addr, - csum_partial((char *)dh, - skb->len, - skb->csum)); - ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); - err = ip6_xmit(sk, skb, &fl, opt, 0); - if (err == NET_XMIT_CN) - err = 0; + + dh->dccph_checksum = dccp_v6_csum_finish(skb, + &ireq->ir_v6_loc_addr, + &ireq->ir_v6_rmt_addr); + fl6.daddr = ireq->ir_v6_rmt_addr; + err = ip6_xmit(sk, skb, &fl6, np->opt, np->tclass); + err = net_xmit_eval(err); } done: - if (opt && opt != np->opt) - sock_kfree_s(sk, opt, opt->tot_len); + dst_release(dst); return err; } static void dccp_v6_reqsk_destructor(struct request_sock *req) { - if (inet6_rsk(req)->pktopts != NULL) - kfree_skb(inet6_rsk(req)->pktopts); + dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); + kfree_skb(inet_rsk(req)->pktopts); } -static struct request_sock_ops dccp6_request_sock_ops = { - .family = AF_INET6, - .obj_size = sizeof(struct dccp6_request_sock), - .rtx_syn_ack = dccp_v6_send_response, - .send_ack = dccp_v6_reqsk_send_ack, - .destructor = dccp_v6_reqsk_destructor, - .send_reset = dccp_v6_ctl_send_reset, -}; - -static struct timewait_sock_ops dccp6_timewait_sock_ops = { - .twsk_obj_size = sizeof(struct dccp6_timewait_sock), -}; - -static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb) +static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb) { - struct ipv6_pinfo *np = inet6_sk(sk); - struct dccp_hdr *dh = dccp_hdr(skb); - - dh->dccph_checksum = csum_ipv6_magic(&np->saddr, &np->daddr, - len, IPPROTO_DCCP, - csum_partial((char *)dh, - dh->dccph_doff << 2, - skb->csum)); -} - -static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb) -{ - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; - const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_reset); + const struct ipv6hdr *rxip6h; struct sk_buff *skb; - struct flowi fl; - u64 seqno; + struct flowi6 fl6; + struct net *net = dev_net(skb_dst(rxskb)->dev); + struct sock *ctl_sk = net->dccp.v6_ctl_sk; + struct dst_entry *dst; - if (rxdh->dccph_type == DCCP_PKT_RESET) + if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) return; if (!ipv6_unicast_destination(rxskb)) - return; + return; - /* - * We need to grab some memory, and put together an RST, - * and then put it into the queue to be sent. - */ + skb = dccp_ctl_make_reset(ctl_sk, rxskb); + if (skb == NULL) + return; - skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + - dccp_hdr_reset_len, GFP_ATOMIC); - if (skb == NULL) - return; + rxip6h = ipv6_hdr(rxskb); + dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr, + &rxip6h->daddr); - skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) + - dccp_hdr_reset_len); + memset(&fl6, 0, sizeof(fl6)); + fl6.daddr = rxip6h->saddr; + fl6.saddr = rxip6h->daddr; - skb->h.raw = skb_push(skb, dccp_hdr_reset_len); - dh = dccp_hdr(skb); - memset(dh, 0, dccp_hdr_reset_len); - - /* Swap the send and the receive. */ - dh->dccph_type = DCCP_PKT_RESET; - dh->dccph_sport = rxdh->dccph_dport; - dh->dccph_dport = rxdh->dccph_sport; - dh->dccph_doff = dccp_hdr_reset_len / 4; - dh->dccph_x = 1; - dccp_hdr_reset(skb)->dccph_reset_code = - DCCP_SKB_CB(rxskb)->dccpd_reset_code; - - /* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */ - seqno = 0; - if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) - dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1); - - dccp_hdr_set_seq(dh, seqno); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), - DCCP_SKB_CB(rxskb)->dccpd_seq); - - memset(&fl, 0, sizeof(fl)); - ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr); - ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr); - dh->dccph_checksum = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, - sizeof(*dh), IPPROTO_DCCP, - skb->csum); - fl.proto = IPPROTO_DCCP; - fl.oif = inet6_iif(rxskb); - fl.fl_ip_dport = dh->dccph_dport; - fl.fl_ip_sport = dh->dccph_sport; + fl6.flowi6_proto = IPPROTO_DCCP; + fl6.flowi6_oif = inet6_iif(rxskb); + fl6.fl6_dport = dccp_hdr(skb)->dccph_dport; + fl6.fl6_sport = dccp_hdr(skb)->dccph_sport; + security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6)); /* sk = NULL, but it is safe for now. RST socket required. */ - if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) { - if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) { - ip6_xmit(NULL, skb, &fl, NULL, 0); - DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); - DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); - return; - } - } - - kfree_skb(skb); -} - -static void dccp_v6_ctl_send_ack(struct sk_buff *rxskb) -{ - struct flowi fl; - struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; - const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_ack_bits); - struct sk_buff *skb; - - skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + - dccp_hdr_ack_len, GFP_ATOMIC); - if (skb == NULL) + dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); + if (!IS_ERR(dst)) { + skb_dst_set(skb, dst); + ip6_xmit(ctl_sk, skb, &fl6, NULL, 0); + DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); + DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); return; - - skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) + - dccp_hdr_ack_len); - - skb->h.raw = skb_push(skb, dccp_hdr_ack_len); - dh = dccp_hdr(skb); - memset(dh, 0, dccp_hdr_ack_len); - - /* Build DCCP header and checksum it. */ - dh->dccph_type = DCCP_PKT_ACK; - dh->dccph_sport = rxdh->dccph_dport; - dh->dccph_dport = rxdh->dccph_sport; - dh->dccph_doff = dccp_hdr_ack_len / 4; - dh->dccph_x = 1; - - dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), - DCCP_SKB_CB(rxskb)->dccpd_seq); - - memset(&fl, 0, sizeof(fl)); - ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr); - ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr); - - /* FIXME: calculate checksum, IPv4 also should... */ - - fl.proto = IPPROTO_DCCP; - fl.oif = inet6_iif(rxskb); - fl.fl_ip_dport = dh->dccph_dport; - fl.fl_ip_sport = dh->dccph_sport; - - if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) { - if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) { - ip6_xmit(NULL, skb, &fl, NULL, 0); - DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); - return; - } } kfree_skb(skb); } -static void dccp_v6_reqsk_send_ack(struct sk_buff *skb, - struct request_sock *req) -{ - dccp_v6_ctl_send_ack(skb); -} +static struct request_sock_ops dccp6_request_sock_ops = { + .family = AF_INET6, + .obj_size = sizeof(struct dccp6_request_sock), + .rtx_syn_ack = dccp_v6_send_response, + .send_ack = dccp_reqsk_send_ack, + .destructor = dccp_v6_reqsk_destructor, + .send_reset = dccp_v6_ctl_send_reset, + .syn_ack_timeout = dccp_syn_ack_timeout, +}; static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) { const struct dccp_hdr *dh = dccp_hdr(skb); - const struct ipv6hdr *iph = skb->nh.ipv6h; + const struct ipv6hdr *iph = ipv6_hdr(skb); struct sock *nsk; struct request_sock **prev; /* Find possible connection requests. */ @@ -652,17 +341,16 @@ static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) if (req != NULL) return dccp_check_req(sk, skb, req, prev); - nsk = __inet6_lookup_established(&dccp_hashinfo, + nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo, &iph->saddr, dh->dccph_sport, &iph->daddr, ntohs(dh->dccph_dport), inet6_iif(skb)); - if (nsk != NULL) { if (nsk->sk_state != DCCP_TIME_WAIT) { bh_lock_sock(nsk); return nsk; } - inet_twsk_put((struct inet_timewait_sock *)nsk); + inet_twsk_put(inet_twsk(nsk)); return NULL; } @@ -671,78 +359,78 @@ static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb) { - struct inet_request_sock *ireq; - struct dccp_sock dp; struct request_sock *req; struct dccp_request_sock *dreq; - struct inet6_request_sock *ireq6; + struct inet_request_sock *ireq; struct ipv6_pinfo *np = inet6_sk(sk); - const __u32 service = dccp_hdr_request(skb)->dccph_req_service; + const __be32 service = dccp_hdr_request(skb)->dccph_req_service; struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); - __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY; if (skb->protocol == htons(ETH_P_IP)) return dccp_v4_conn_request(sk, skb); if (!ipv6_unicast_destination(skb)) - goto drop; + return 0; /* discard, don't send a reset here */ if (dccp_bad_service_code(sk, service)) { - reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; + dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; goto drop; - } + } /* - * There are no SYN attacks on IPv6, yet... + * There are no SYN attacks on IPv6, yet... */ + dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; if (inet_csk_reqsk_queue_is_full(sk)) - goto drop; + goto drop; if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) goto drop; - req = inet6_reqsk_alloc(sk->sk_prot->rsk_prot); + req = inet6_reqsk_alloc(&dccp6_request_sock_ops); if (req == NULL) goto drop; - /* FIXME: process options */ + if (dccp_reqsk_init(req, dccp_sk(sk), skb)) + goto drop_and_free; - dccp_openreq_init(req, &dp, skb); + dreq = dccp_rsk(req); + if (dccp_parse_options(sk, dreq, skb)) + goto drop_and_free; + + if (security_inet_conn_request(sk, skb, req)) + goto drop_and_free; - ireq6 = inet6_rsk(req); ireq = inet_rsk(req); - ipv6_addr_copy(&ireq6->rmt_addr, &skb->nh.ipv6h->saddr); - ipv6_addr_copy(&ireq6->loc_addr, &skb->nh.ipv6h->daddr); - req->rcv_wnd = 100; /* Fake, option parsing will get the - right value */ - ireq6->pktopts = NULL; + ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; + ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; if (ipv6_opt_accepted(sk, skb) || np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { atomic_inc(&skb->users); - ireq6->pktopts = skb; + ireq->pktopts = skb; } - ireq6->iif = sk->sk_bound_dev_if; + ireq->ir_iif = sk->sk_bound_dev_if; /* So that link locals have meaning */ if (!sk->sk_bound_dev_if && - ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL) - ireq6->iif = inet6_iif(skb); + ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) + ireq->ir_iif = inet6_iif(skb); - /* + /* * Step 3: Process LISTEN state * - * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie * - * In fact we defer setting S.GSR, S.SWL, S.SWH to - * dccp_create_openreq_child. + * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). */ - dreq = dccp_rsk(req); dreq->dreq_isr = dcb->dccpd_seq; - dreq->dreq_iss = dccp_v6_init_sequence(sk, skb); + dreq->dreq_gsr = dreq->dreq_isr; + dreq->dreq_iss = dccp_v6_init_sequence(skb); + dreq->dreq_gss = dreq->dreq_iss; dreq->dreq_service = service; - if (dccp_v6_send_response(sk, req, NULL)) + if (dccp_v6_send_response(sk, req)) goto drop_and_free; inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); @@ -752,7 +440,6 @@ drop_and_free: reqsk_free(req); drop: DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); - dcb->dccpd_reset_code = reset_code; return -1; } @@ -761,45 +448,39 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk, struct request_sock *req, struct dst_entry *dst) { - struct inet6_request_sock *ireq6 = inet6_rsk(req); + struct inet_request_sock *ireq = inet_rsk(req); struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct inet_sock *newinet; - struct dccp_sock *newdp; struct dccp6_sock *newdp6; struct sock *newsk; - struct ipv6_txoptions *opt; if (skb->protocol == htons(ETH_P_IP)) { /* * v6 mapped */ - newsk = dccp_v4_request_recv_sock(sk, skb, req, dst); - if (newsk == NULL) + if (newsk == NULL) return NULL; newdp6 = (struct dccp6_sock *)newsk; - newdp = dccp_sk(newsk); newinet = inet_sk(newsk); newinet->pinet6 = &newdp6->inet6; newnp = inet6_sk(newsk); memcpy(newnp, np, sizeof(struct ipv6_pinfo)); - ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF), - newinet->daddr); + ipv6_addr_set_v4mapped(newinet->inet_daddr, &newsk->sk_v6_daddr); - ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF), - newinet->saddr); + ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr); - ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr); + newsk->sk_v6_rcv_saddr = newnp->saddr; inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped; newsk->sk_backlog_rcv = dccp_v4_do_rcv; newnp->pktoptions = NULL; newnp->opt = NULL; newnp->mcast_oif = inet6_iif(skb); - newnp->mcast_hops = skb->nh.ipv6h->hop_limit; + newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; /* * No need to charge this sock to the relevant IPv6 refcnt debug socks count @@ -816,51 +497,32 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk, return newsk; } - opt = np->opt; if (sk_acceptq_is_full(sk)) goto out_overflow; - if (np->rxopt.bits.osrcrt == 2 && - opt == NULL && ireq6->pktopts) { - struct inet6_skb_parm *rxopt = IP6CB(ireq6->pktopts); - if (rxopt->srcrt) - opt = ipv6_invert_rthdr(sk, - (struct ipv6_rt_hdr *)(ireq6->pktopts->nh.raw + - rxopt->srcrt)); - } - if (dst == NULL) { - struct in6_addr *final_p = NULL, final; - struct flowi fl; - - memset(&fl, 0, sizeof(fl)); - fl.proto = IPPROTO_DCCP; - ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } - ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); - fl.oif = sk->sk_bound_dev_if; - fl.fl_ip_dport = inet_rsk(req)->rmt_port; - fl.fl_ip_sport = inet_sk(sk)->sport; - - if (ip6_dst_lookup(sk, &dst, &fl)) - goto out; - - if (final_p) - ipv6_addr_copy(&fl.fl6_dst, final_p); - - if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0) + struct in6_addr *final_p, final; + struct flowi6 fl6; + + memset(&fl6, 0, sizeof(fl6)); + fl6.flowi6_proto = IPPROTO_DCCP; + fl6.daddr = ireq->ir_v6_rmt_addr; + final_p = fl6_update_dst(&fl6, np->opt, &final); + fl6.saddr = ireq->ir_v6_loc_addr; + fl6.flowi6_oif = sk->sk_bound_dev_if; + fl6.fl6_dport = ireq->ir_rmt_port; + fl6.fl6_sport = htons(ireq->ir_num); + security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); + + dst = ip6_dst_lookup_flow(sk, &fl6, final_p); + if (IS_ERR(dst)) goto out; - } + } newsk = dccp_create_openreq_child(sk, req, skb); if (newsk == NULL) - goto out; + goto out_nonewsk; /* * No need to charge this sock to the relevant IPv6 refcnt debug socks @@ -868,78 +530,77 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk, * comment in that function for the gory details. -acme */ - ip6_dst_store(newsk, dst, NULL); - newsk->sk_route_caps = dst->dev->features & - ~(NETIF_F_IP_CSUM | NETIF_F_TSO); - + __ip6_dst_store(newsk, dst, NULL, NULL); + newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM | + NETIF_F_TSO); newdp6 = (struct dccp6_sock *)newsk; newinet = inet_sk(newsk); newinet->pinet6 = &newdp6->inet6; - newdp = dccp_sk(newsk); newnp = inet6_sk(newsk); memcpy(newnp, np, sizeof(struct ipv6_pinfo)); - ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr); - ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr); - ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr); - newsk->sk_bound_dev_if = ireq6->iif; + newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; + newnp->saddr = ireq->ir_v6_loc_addr; + newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; + newsk->sk_bound_dev_if = ireq->ir_iif; - /* Now IPv6 options... + /* Now IPv6 options... First: no IPv4 options. */ - newinet->opt = NULL; + newinet->inet_opt = NULL; /* Clone RX bits */ newnp->rxopt.all = np->rxopt.all; /* Clone pktoptions received with SYN */ newnp->pktoptions = NULL; - if (ireq6->pktopts != NULL) { - newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC); - kfree_skb(ireq6->pktopts); - ireq6->pktopts = NULL; + if (ireq->pktopts != NULL) { + newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC); + consume_skb(ireq->pktopts); + ireq->pktopts = NULL; if (newnp->pktoptions) skb_set_owner_r(newnp->pktoptions, newsk); } newnp->opt = NULL; newnp->mcast_oif = inet6_iif(skb); - newnp->mcast_hops = skb->nh.ipv6h->hop_limit; + newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; - /* Clone native IPv6 options from listening socket (if any) - - Yes, keeping reference count would be much more clever, - but we make one more one thing there: reattach optmem - to newsk. + /* + * Clone native IPv6 options from listening socket (if any) + * + * Yes, keeping reference count would be much more clever, but we make + * one more one thing there: reattach optmem to newsk. */ - if (opt) { - newnp->opt = ipv6_dup_options(newsk, opt); - if (opt != np->opt) - sock_kfree_s(sk, opt, opt->tot_len); - } + if (np->opt != NULL) + newnp->opt = ipv6_dup_options(newsk, np->opt); inet_csk(newsk)->icsk_ext_hdr_len = 0; - if (newnp->opt) + if (newnp->opt != NULL) inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + newnp->opt->opt_flen); dccp_sync_mss(newsk, dst_mtu(dst)); - newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6; + newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; + newinet->inet_rcv_saddr = LOOPBACK4_IPV6; - __inet6_hash(&dccp_hashinfo, newsk); - inet_inherit_port(&dccp_hashinfo, sk, newsk); + if (__inet_inherit_port(sk, newsk) < 0) { + inet_csk_prepare_forced_close(newsk); + dccp_done(newsk); + goto out; + } + __inet6_hash(newsk, NULL); return newsk; out_overflow: - NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); -out: - NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); - if (opt && opt != np->opt) - sock_kfree_s(sk, opt, opt->tot_len); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); +out_nonewsk: dst_release(dst); +out: + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); return NULL; } @@ -967,12 +628,12 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) if (skb->protocol == htons(ETH_P_IP)) return dccp_v4_do_rcv(sk, skb); - if (sk_filter(sk, skb, 0)) + if (sk_filter(sk, skb)) goto discard; /* - * socket locking is here for SMP purposes as backlog rcv - * is currently called with bh processing disabled. + * socket locking is here for SMP purposes as backlog rcv is currently + * called with bh processing disabled. */ /* Do Stevens' IPV6_PKTOPTIONS. @@ -986,31 +647,63 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) looks not very well thought. For now we latch options, received in the last packet, enqueued by tcp. Feel free to propose better solution. - --ANK (980728) + --ANK (980728) */ if (np->rxopt.all) + /* + * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below + * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example. + */ opt_skb = skb_clone(skb, GFP_ATOMIC); if (sk->sk_state == DCCP_OPEN) { /* Fast path */ if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len)) goto reset; + if (opt_skb) { + /* XXX This is where we would goto ipv6_pktoptions. */ + __kfree_skb(opt_skb); + } return 0; } - if (sk->sk_state == DCCP_LISTEN) { + /* + * Step 3: Process LISTEN state + * If S.state == LISTEN, + * If P.type == Request or P contains a valid Init Cookie option, + * (* Must scan the packet's options to check for Init + * Cookies. Only Init Cookies are processed here, + * however; other options are processed in Step 8. This + * scan need only be performed if the endpoint uses Init + * Cookies *) + * (* Generate a new socket and switch to that socket *) + * Set S := new socket for this port pair + * S.state = RESPOND + * Choose S.ISS (initial seqno) or set from Init Cookies + * Initialize S.GAR := S.ISS + * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies + * Continue with S.state == RESPOND + * (* A Response packet will be generated in Step 11 *) + * Otherwise, + * Generate Reset(No Connection) unless P.type == Reset + * Drop packet and return + * + * NOTE: the check for the packet types is done in + * dccp_rcv_state_process + */ + if (sk->sk_state == DCCP_LISTEN) { struct sock *nsk = dccp_v6_hnd_req(sk, skb); - if (!nsk) - goto discard; + if (nsk == NULL) + goto discard; /* * Queue it on the new socket if the new socket is active, * otherwise we just shortcircuit this and continue with * the new socket.. */ - if(nsk != sk) { + if (nsk != sk) { if (dccp_child_process(sk, nsk, skb)) goto reset; - if (opt_skb) + if (opt_skb != NULL) __kfree_skb(opt_skb); return 0; } @@ -1018,31 +711,42 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len)) goto reset; + if (opt_skb) { + /* XXX This is where we would goto ipv6_pktoptions. */ + __kfree_skb(opt_skb); + } return 0; reset: - dccp_v6_ctl_send_reset(skb); + dccp_v6_ctl_send_reset(sk, skb); discard: - if (opt_skb) + if (opt_skb != NULL) __kfree_skb(opt_skb); kfree_skb(skb); return 0; } -static int dccp_v6_rcv(struct sk_buff **pskb) +static int dccp_v6_rcv(struct sk_buff *skb) { const struct dccp_hdr *dh; - struct sk_buff *skb = *pskb; struct sock *sk; + int min_cov; - /* Step 1: Check header basics: */ + /* Step 1: Check header basics */ if (dccp_invalid_packet(skb)) goto discard_it; + /* Step 1: If header checksum is incorrect, drop packet and return. */ + if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr)) { + DCCP_WARN("dropped packet with invalid checksum\n"); + goto discard_it; + } + dh = dccp_hdr(skb); - DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb); + DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; if (dccp_packet_without_ack(skb)) @@ -1051,93 +755,269 @@ static int dccp_v6_rcv(struct sk_buff **pskb) DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); /* Step 2: - * Look up flow ID in table and get corresponding socket */ - sk = __inet6_lookup(&dccp_hashinfo, &skb->nh.ipv6h->saddr, - dh->dccph_sport, - &skb->nh.ipv6h->daddr, ntohs(dh->dccph_dport), - inet6_iif(skb)); - /* + * Look up flow ID in table and get corresponding socket */ + sk = __inet6_lookup_skb(&dccp_hashinfo, skb, + dh->dccph_sport, dh->dccph_dport); + /* * Step 2: - * If no socket ... - * Generate Reset(No Connection) unless P.type == Reset - * Drop packet and return + * If no socket ... */ - if (sk == NULL) + if (sk == NULL) { + dccp_pr_debug("failed to look up flow ID in table and " + "get corresponding socket\n"); goto no_dccp_socket; + } - /* + /* * Step 2: - * ... or S.state == TIMEWAIT, + * ... or S.state == TIMEWAIT, * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ - - if (sk->sk_state == DCCP_TIME_WAIT) - goto do_time_wait; + if (sk->sk_state == DCCP_TIME_WAIT) { + dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); + inet_twsk_put(inet_twsk(sk)); + goto no_dccp_socket; + } + + /* + * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage + * o if MinCsCov = 0, only packets with CsCov = 0 are accepted + * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov + */ + min_cov = dccp_sk(sk)->dccps_pcrlen; + if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { + dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", + dh->dccph_cscov, min_cov); + /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */ + goto discard_and_relse; + } if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) goto discard_and_relse; - return sk_receive_skb(sk, skb) ? -1 : 0; + return sk_receive_skb(sk, skb, 1) ? -1 : 0; no_dccp_socket: if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) goto discard_it; /* * Step 2: + * If no socket ... * Generate Reset(No Connection) unless P.type == Reset * Drop packet and return */ if (dh->dccph_type != DCCP_PKT_RESET) { DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION; - dccp_v6_ctl_send_reset(skb); + dccp_v6_ctl_send_reset(sk, skb); } -discard_it: - - /* - * Discard frame - */ +discard_it: kfree_skb(skb); return 0; discard_and_relse: sock_put(sk); goto discard_it; +} + +static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, + int addr_len) +{ + struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr; + struct inet_connection_sock *icsk = inet_csk(sk); + struct inet_sock *inet = inet_sk(sk); + struct ipv6_pinfo *np = inet6_sk(sk); + struct dccp_sock *dp = dccp_sk(sk); + struct in6_addr *saddr = NULL, *final_p, final; + struct flowi6 fl6; + struct dst_entry *dst; + int addr_type; + int err; + + dp->dccps_role = DCCP_ROLE_CLIENT; -do_time_wait: - inet_twsk_put((struct inet_timewait_sock *)sk); - goto no_dccp_socket; + if (addr_len < SIN6_LEN_RFC2133) + return -EINVAL; + + if (usin->sin6_family != AF_INET6) + return -EAFNOSUPPORT; + + memset(&fl6, 0, sizeof(fl6)); + + if (np->sndflow) { + fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; + IP6_ECN_flow_init(fl6.flowlabel); + if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) { + struct ip6_flowlabel *flowlabel; + flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); + if (flowlabel == NULL) + return -EINVAL; + fl6_sock_release(flowlabel); + } + } + /* + * connect() to INADDR_ANY means loopback (BSD'ism). + */ + if (ipv6_addr_any(&usin->sin6_addr)) + usin->sin6_addr.s6_addr[15] = 1; + + addr_type = ipv6_addr_type(&usin->sin6_addr); + + if (addr_type & IPV6_ADDR_MULTICAST) + return -ENETUNREACH; + + if (addr_type & IPV6_ADDR_LINKLOCAL) { + if (addr_len >= sizeof(struct sockaddr_in6) && + usin->sin6_scope_id) { + /* If interface is set while binding, indices + * must coincide. + */ + if (sk->sk_bound_dev_if && + sk->sk_bound_dev_if != usin->sin6_scope_id) + return -EINVAL; + + sk->sk_bound_dev_if = usin->sin6_scope_id; + } + + /* Connect to link-local address requires an interface */ + if (!sk->sk_bound_dev_if) + return -EINVAL; + } + + sk->sk_v6_daddr = usin->sin6_addr; + np->flow_label = fl6.flowlabel; + + /* + * DCCP over IPv4 + */ + if (addr_type == IPV6_ADDR_MAPPED) { + u32 exthdrlen = icsk->icsk_ext_hdr_len; + struct sockaddr_in sin; + + SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); + + if (__ipv6_only_sock(sk)) + return -ENETUNREACH; + + sin.sin_family = AF_INET; + sin.sin_port = usin->sin6_port; + sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; + + icsk->icsk_af_ops = &dccp_ipv6_mapped; + sk->sk_backlog_rcv = dccp_v4_do_rcv; + + err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); + if (err) { + icsk->icsk_ext_hdr_len = exthdrlen; + icsk->icsk_af_ops = &dccp_ipv6_af_ops; + sk->sk_backlog_rcv = dccp_v6_do_rcv; + goto failure; + } + ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); + ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &sk->sk_v6_rcv_saddr); + + return err; + } + + if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) + saddr = &sk->sk_v6_rcv_saddr; + + fl6.flowi6_proto = IPPROTO_DCCP; + fl6.daddr = sk->sk_v6_daddr; + fl6.saddr = saddr ? *saddr : np->saddr; + fl6.flowi6_oif = sk->sk_bound_dev_if; + fl6.fl6_dport = usin->sin6_port; + fl6.fl6_sport = inet->inet_sport; + security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); + + final_p = fl6_update_dst(&fl6, np->opt, &final); + + dst = ip6_dst_lookup_flow(sk, &fl6, final_p); + if (IS_ERR(dst)) { + err = PTR_ERR(dst); + goto failure; + } + + if (saddr == NULL) { + saddr = &fl6.saddr; + sk->sk_v6_rcv_saddr = *saddr; + } + + /* set the source address */ + np->saddr = *saddr; + inet->inet_rcv_saddr = LOOPBACK4_IPV6; + + __ip6_dst_store(sk, dst, NULL, NULL); + + icsk->icsk_ext_hdr_len = 0; + if (np->opt != NULL) + icsk->icsk_ext_hdr_len = (np->opt->opt_flen + + np->opt->opt_nflen); + + inet->inet_dport = usin->sin6_port; + + dccp_set_state(sk, DCCP_REQUESTING); + err = inet6_hash_connect(&dccp_death_row, sk); + if (err) + goto late_failure; + + dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32, + sk->sk_v6_daddr.s6_addr32, + inet->inet_sport, + inet->inet_dport); + err = dccp_connect(sk); + if (err) + goto late_failure; + + return 0; + +late_failure: + dccp_set_state(sk, DCCP_CLOSED); + __sk_dst_reset(sk); +failure: + inet->inet_dport = 0; + sk->sk_route_caps = 0; + return err; } -static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = { - .queue_xmit = inet6_csk_xmit, - .send_check = dccp_v6_send_check, - .rebuild_header = inet6_sk_rebuild_header, - .conn_request = dccp_v6_conn_request, - .syn_recv_sock = dccp_v6_request_recv_sock, - .net_header_len = sizeof(struct ipv6hdr), - .setsockopt = ipv6_setsockopt, - .getsockopt = ipv6_getsockopt, - .addr2sockaddr = inet6_csk_addr2sockaddr, - .sockaddr_len = sizeof(struct sockaddr_in6) +static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = { + .queue_xmit = inet6_csk_xmit, + .send_check = dccp_v6_send_check, + .rebuild_header = inet6_sk_rebuild_header, + .conn_request = dccp_v6_conn_request, + .syn_recv_sock = dccp_v6_request_recv_sock, + .net_header_len = sizeof(struct ipv6hdr), + .setsockopt = ipv6_setsockopt, + .getsockopt = ipv6_getsockopt, + .addr2sockaddr = inet6_csk_addr2sockaddr, + .sockaddr_len = sizeof(struct sockaddr_in6), + .bind_conflict = inet6_csk_bind_conflict, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_ipv6_setsockopt, + .compat_getsockopt = compat_ipv6_getsockopt, +#endif }; /* * DCCP over IPv4 via INET6 API */ -static struct inet_connection_sock_af_ops dccp_ipv6_mapped = { - .queue_xmit = ip_queue_xmit, - .send_check = dccp_v4_send_check, - .rebuild_header = inet_sk_rebuild_header, - .conn_request = dccp_v6_conn_request, - .syn_recv_sock = dccp_v6_request_recv_sock, - .net_header_len = sizeof(struct iphdr), - .setsockopt = ipv6_setsockopt, - .getsockopt = ipv6_getsockopt, - .addr2sockaddr = inet6_csk_addr2sockaddr, - .sockaddr_len = sizeof(struct sockaddr_in6) +static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = { + .queue_xmit = ip_queue_xmit, + .send_check = dccp_v4_send_check, + .rebuild_header = inet_sk_rebuild_header, + .conn_request = dccp_v6_conn_request, + .syn_recv_sock = dccp_v6_request_recv_sock, + .net_header_len = sizeof(struct iphdr), + .setsockopt = ipv6_setsockopt, + .getsockopt = ipv6_getsockopt, + .addr2sockaddr = inet6_csk_addr2sockaddr, + .sockaddr_len = sizeof(struct sockaddr_in6), +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_ipv6_setsockopt, + .compat_getsockopt = compat_ipv6_getsockopt, +#endif }; /* NOTE: A lot of things set to zero explicitly by call to @@ -1145,71 +1025,89 @@ static struct inet_connection_sock_af_ops dccp_ipv6_mapped = { */ static int dccp_v6_init_sock(struct sock *sk) { - int err = dccp_v4_init_sock(sk); + static __u8 dccp_v6_ctl_sock_initialized; + int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized); - if (err == 0) + if (err == 0) { + if (unlikely(!dccp_v6_ctl_sock_initialized)) + dccp_v6_ctl_sock_initialized = 1; inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops; + } return err; } -static int dccp_v6_destroy_sock(struct sock *sk) +static void dccp_v6_destroy_sock(struct sock *sk) { - dccp_v4_destroy_sock(sk); - return inet6_destroy_sock(sk); + dccp_destroy_sock(sk); + inet6_destroy_sock(sk); } +static struct timewait_sock_ops dccp6_timewait_sock_ops = { + .twsk_obj_size = sizeof(struct dccp6_timewait_sock), +}; + static struct proto dccp_v6_prot = { - .name = "DCCPv6", - .owner = THIS_MODULE, - .close = dccp_close, - .connect = dccp_v6_connect, - .disconnect = dccp_disconnect, - .ioctl = dccp_ioctl, - .init = dccp_v6_init_sock, - .setsockopt = dccp_setsockopt, - .getsockopt = dccp_getsockopt, - .sendmsg = dccp_sendmsg, - .recvmsg = dccp_recvmsg, - .backlog_rcv = dccp_v6_do_rcv, - .hash = dccp_v6_hash, - .unhash = dccp_unhash, - .accept = inet_csk_accept, - .get_port = dccp_v6_get_port, - .shutdown = dccp_shutdown, - .destroy = dccp_v6_destroy_sock, - .orphan_count = &dccp_orphan_count, - .max_header = MAX_DCCP_HEADER, - .obj_size = sizeof(struct dccp6_sock), - .rsk_prot = &dccp6_request_sock_ops, - .twsk_prot = &dccp6_timewait_sock_ops, + .name = "DCCPv6", + .owner = THIS_MODULE, + .close = dccp_close, + .connect = dccp_v6_connect, + .disconnect = dccp_disconnect, + .ioctl = dccp_ioctl, + .init = dccp_v6_init_sock, + .setsockopt = dccp_setsockopt, + .getsockopt = dccp_getsockopt, + .sendmsg = dccp_sendmsg, + .recvmsg = dccp_recvmsg, + .backlog_rcv = dccp_v6_do_rcv, + .hash = dccp_v6_hash, + .unhash = inet_unhash, + .accept = inet_csk_accept, + .get_port = inet_csk_get_port, + .shutdown = dccp_shutdown, + .destroy = dccp_v6_destroy_sock, + .orphan_count = &dccp_orphan_count, + .max_header = MAX_DCCP_HEADER, + .obj_size = sizeof(struct dccp6_sock), + .slab_flags = SLAB_DESTROY_BY_RCU, + .rsk_prot = &dccp6_request_sock_ops, + .twsk_prot = &dccp6_timewait_sock_ops, + .h.hashinfo = &dccp_hashinfo, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_dccp_setsockopt, + .compat_getsockopt = compat_dccp_getsockopt, +#endif }; -static struct inet6_protocol dccp_v6_protocol = { - .handler = dccp_v6_rcv, - .err_handler = dccp_v6_err, - .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, +static const struct inet6_protocol dccp_v6_protocol = { + .handler = dccp_v6_rcv, + .err_handler = dccp_v6_err, + .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, }; -static struct proto_ops inet6_dccp_ops = { - .family = PF_INET6, - .owner = THIS_MODULE, - .release = inet6_release, - .bind = inet6_bind, - .connect = inet_stream_connect, - .socketpair = sock_no_socketpair, - .accept = inet_accept, - .getname = inet6_getname, - .poll = dccp_poll, - .ioctl = inet6_ioctl, - .listen = inet_dccp_listen, - .shutdown = inet_shutdown, - .setsockopt = sock_common_setsockopt, - .getsockopt = sock_common_getsockopt, - .sendmsg = inet_sendmsg, - .recvmsg = sock_common_recvmsg, - .mmap = sock_no_mmap, - .sendpage = sock_no_sendpage, +static const struct proto_ops inet6_dccp_ops = { + .family = PF_INET6, + .owner = THIS_MODULE, + .release = inet6_release, + .bind = inet6_bind, + .connect = inet_stream_connect, + .socketpair = sock_no_socketpair, + .accept = inet_accept, + .getname = inet6_getname, + .poll = dccp_poll, + .ioctl = inet6_ioctl, + .listen = inet_dccp_listen, + .shutdown = inet_shutdown, + .setsockopt = sock_common_setsockopt, + .getsockopt = sock_common_getsockopt, + .sendmsg = inet_sendmsg, + .recvmsg = sock_common_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +#ifdef CONFIG_COMPAT + .compat_setsockopt = compat_sock_common_setsockopt, + .compat_getsockopt = compat_sock_common_getsockopt, +#endif }; static struct inet_protosw dccp_v6_protosw = { @@ -1217,10 +1115,28 @@ static struct inet_protosw dccp_v6_protosw = { .protocol = IPPROTO_DCCP, .prot = &dccp_v6_prot, .ops = &inet6_dccp_ops, - .capability = -1, .flags = INET_PROTOSW_ICSK, }; +static int __net_init dccp_v6_init_net(struct net *net) +{ + if (dccp_hashinfo.bhash == NULL) + return -ESOCKTNOSUPPORT; + + return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6, + SOCK_DCCP, IPPROTO_DCCP, net); +} + +static void __net_exit dccp_v6_exit_net(struct net *net) +{ + inet_ctl_sock_destroy(net->dccp.v6_ctl_sk); +} + +static struct pernet_operations dccp_v6_ops = { + .init = dccp_v6_init_net, + .exit = dccp_v6_exit_net, +}; + static int __init dccp_v6_init(void) { int err = proto_register(&dccp_v6_prot, 1); @@ -1233,8 +1149,16 @@ static int __init dccp_v6_init(void) goto out_unregister_proto; inet6_register_protosw(&dccp_v6_protosw); + + err = register_pernet_subsys(&dccp_v6_ops); + if (err != 0) + goto out_destroy_ctl_sock; out: return err; + +out_destroy_ctl_sock: + inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP); + inet6_unregister_protosw(&dccp_v6_protosw); out_unregister_proto: proto_unregister(&dccp_v6_prot); goto out; @@ -1242,6 +1166,7 @@ out_unregister_proto: static void __exit dccp_v6_exit(void) { + unregister_pernet_subsys(&dccp_v6_ops); inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP); inet6_unregister_protosw(&dccp_v6_protosw); proto_unregister(&dccp_v6_prot); @@ -1255,8 +1180,8 @@ module_exit(dccp_v6_exit); * values directly, Also cover the case where the protocol is not specified, * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP */ -MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6"); -MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol"); diff --git a/net/dccp/ipv6.h b/net/dccp/ipv6.h index e4d4e930927..af259e15e7f 100644 --- a/net/dccp/ipv6.h +++ b/net/dccp/ipv6.h @@ -11,7 +11,6 @@ * published by the Free Software Foundation. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/ipv6.h> @@ -26,12 +25,10 @@ struct dccp6_sock { struct dccp6_request_sock { struct dccp_request_sock dccp; - struct inet6_request_sock inet6; }; struct dccp6_timewait_sock { struct inet_timewait_sock inet; - struct inet6_timewait_sock tw6; }; #endif /* _DCCP_IPV6_H */ diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c index 29261fc198e..c69eb9c4fbb 100644 --- a/net/dccp/minisocks.c +++ b/net/dccp/minisocks.c @@ -10,8 +10,9 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> +#include <linux/gfp.h> +#include <linux/kernel.h> #include <linux/skbuff.h> #include <linux/timer.h> @@ -22,17 +23,17 @@ #include "ackvec.h" #include "ccid.h" #include "dccp.h" +#include "feat.h" struct inet_timewait_death_row dccp_death_row = { .sysctl_max_tw_buckets = NR_FILE * 2, .period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS, - .death_lock = SPIN_LOCK_UNLOCKED, + .death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock), .hashinfo = &dccp_hashinfo, .tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0, (unsigned long)&dccp_death_row), .twkill_work = __WORK_INITIALIZER(dccp_death_row.twkill_work, - inet_twdr_twkill_work, - &dccp_death_row), + inet_twdr_twkill_work), /* Short-time timewait calendar */ .twcal_hand = -1, @@ -52,15 +53,12 @@ void dccp_time_wait(struct sock *sk, int state, int timeo) if (tw != NULL) { const struct inet_connection_sock *icsk = inet_csk(sk); const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1); -#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +#if IS_ENABLED(CONFIG_IPV6) if (tw->tw_family == PF_INET6) { const struct ipv6_pinfo *np = inet6_sk(sk); - struct inet6_timewait_sock *tw6; - tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot); - tw6 = inet6_twsk((struct sock *)tw); - ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr); - ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr); + tw->tw_v6_daddr = sk->sk_v6_daddr; + tw->tw_v6_rcv_saddr = sk->sk_v6_rcv_saddr; tw->tw_ipv6only = np->ipv6only; } #endif @@ -83,8 +81,7 @@ void dccp_time_wait(struct sock *sk, int state, int timeo) * socket up. We've got bigger problems than * non-graceful socket closings. */ - LIMIT_NETDEBUG(KERN_INFO "DCCP: time wait bucket " - "table overflow\n"); + DCCP_WARN("time wait bucket table overflow\n"); } dccp_done(sk); @@ -97,85 +94,52 @@ struct sock *dccp_create_openreq_child(struct sock *sk, /* * Step 3: Process LISTEN state * - * // Generate a new socket and switch to that socket - * Set S := new socket for this port pair + * (* Generate a new socket and switch to that socket *) + * Set S := new socket for this port pair */ - struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC); + struct sock *newsk = inet_csk_clone_lock(sk, req, GFP_ATOMIC); if (newsk != NULL) { - const struct dccp_request_sock *dreq = dccp_rsk(req); - struct inet_connection_sock *newicsk = inet_csk(sk); + struct dccp_request_sock *dreq = dccp_rsk(req); + struct inet_connection_sock *newicsk = inet_csk(newsk); struct dccp_sock *newdp = dccp_sk(newsk); - newdp->dccps_role = DCCP_ROLE_SERVER; - newdp->dccps_hc_rx_ackvec = NULL; - newdp->dccps_service_list = NULL; - newdp->dccps_service = dreq->dreq_service; - newicsk->icsk_rto = DCCP_TIMEOUT_INIT; - do_gettimeofday(&newdp->dccps_epoch); - - if (newdp->dccps_options.dccpo_send_ack_vector) { - newdp->dccps_hc_rx_ackvec = - dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN, - GFP_ATOMIC); - /* - * XXX: We're using the same CCIDs set on the parent, - * i.e. sk_clone copied the master sock and left the - * CCID pointers for this child, that is why we do the - * __ccid_get calls. - */ - if (unlikely(newdp->dccps_hc_rx_ackvec == NULL)) - goto out_free; - } - - if (unlikely(ccid_hc_rx_init(newdp->dccps_hc_rx_ccid, - newsk) != 0 || - ccid_hc_tx_init(newdp->dccps_hc_tx_ccid, - newsk) != 0)) { - dccp_ackvec_free(newdp->dccps_hc_rx_ackvec); - ccid_hc_rx_exit(newdp->dccps_hc_rx_ccid, newsk); - ccid_hc_tx_exit(newdp->dccps_hc_tx_ccid, newsk); -out_free: - /* It is still raw copy of parent, so invalidate - * destructor and make plain sk_free() */ - newsk->sk_destruct = NULL; - sk_free(newsk); - return NULL; - } - - __ccid_get(newdp->dccps_hc_rx_ccid); - __ccid_get(newdp->dccps_hc_tx_ccid); + newdp->dccps_role = DCCP_ROLE_SERVER; + newdp->dccps_hc_rx_ackvec = NULL; + newdp->dccps_service_list = NULL; + newdp->dccps_service = dreq->dreq_service; + newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo; + newdp->dccps_timestamp_time = dreq->dreq_timestamp_time; + newicsk->icsk_rto = DCCP_TIMEOUT_INIT; + INIT_LIST_HEAD(&newdp->dccps_featneg); /* * Step 3: Process LISTEN state * - * Choose S.ISS (initial seqno) or set from Init Cookie - * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init - * Cookie + * Choose S.ISS (initial seqno) or set from Init Cookies + * Initialize S.GAR := S.ISS + * Set S.ISR, S.GSR from packet (or Init Cookies) + * + * Setting AWL/AWH and SWL/SWH happens as part of the feature + * activation below, as these windows all depend on the local + * and remote Sequence Window feature values (7.5.2). */ - - /* See dccp_v4_conn_request */ - newdp->dccps_options.dccpo_sequence_window = req->rcv_wnd; - - newdp->dccps_gar = newdp->dccps_isr = dreq->dreq_isr; - dccp_update_gsr(newsk, dreq->dreq_isr); - newdp->dccps_iss = dreq->dreq_iss; - dccp_update_gss(newsk, dreq->dreq_iss); + newdp->dccps_gss = dreq->dreq_gss; + newdp->dccps_gar = newdp->dccps_iss; + newdp->dccps_isr = dreq->dreq_isr; + newdp->dccps_gsr = dreq->dreq_gsr; /* - * SWL and AWL are initially adjusted so that they are not less than - * the initial Sequence Numbers received and sent, respectively: - * SWL := max(GSR + 1 - floor(W/4), ISR), - * AWL := max(GSS - W' + 1, ISS). - * These adjustments MUST be applied only at the beginning of the - * connection. + * Activate features: initialise CCIDs, sequence windows etc. */ - dccp_set_seqno(&newdp->dccps_swl, - max48(newdp->dccps_swl, newdp->dccps_isr)); - dccp_set_seqno(&newdp->dccps_awl, - max48(newdp->dccps_awl, newdp->dccps_iss)); - + if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) { + /* It is still raw copy of parent, so invalidate + * destructor and make plain sk_free() */ + newsk->sk_destruct = NULL; + sk_free(newsk); + return NULL; + } dccp_init_xmit_timers(newsk); DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS); @@ -185,7 +149,7 @@ out_free: EXPORT_SYMBOL_GPL(dccp_create_openreq_child); -/* +/* * Process an incoming packet for RESPOND sockets represented * as an request_sock. */ @@ -194,19 +158,20 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, struct request_sock **prev) { struct sock *child = NULL; + struct dccp_request_sock *dreq = dccp_rsk(req); /* Check for retransmitted REQUEST */ if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { - if (after48(DCCP_SKB_CB(skb)->dccpd_seq, - dccp_rsk(req)->dreq_isr)) { - struct dccp_request_sock *dreq = dccp_rsk(req); + if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_gsr)) { dccp_pr_debug("Retransmitted REQUEST\n"); - /* Send another RESPONSE packet */ - dccp_set_seqno(&dreq->dreq_iss, dreq->dreq_iss + 1); - dccp_set_seqno(&dreq->dreq_isr, - DCCP_SKB_CB(skb)->dccpd_seq); - req->rsk_ops->rtx_syn_ack(sk, req, NULL); + dreq->dreq_gsr = DCCP_SKB_CB(skb)->dccpd_seq; + /* + * Send another RESPONSE packet + * To protect against Request floods, increment retrans + * counter (backoff, monitored by dccp_response_timer). + */ + inet_rtx_syn_ack(sk, req); } /* Network Duplicate, discard packet */ return NULL; @@ -219,22 +184,24 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, goto drop; /* Invalid ACK */ - if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dccp_rsk(req)->dreq_iss) { + if (!between48(DCCP_SKB_CB(skb)->dccpd_ack_seq, + dreq->dreq_iss, dreq->dreq_gss)) { dccp_pr_debug("Invalid ACK number: ack_seq=%llu, " - "dreq_iss=%llu\n", + "dreq_iss=%llu, dreq_gss=%llu\n", (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq, - (unsigned long long) - dccp_rsk(req)->dreq_iss); + (unsigned long long) dreq->dreq_iss, + (unsigned long long) dreq->dreq_gss); goto drop; } + if (dccp_parse_options(sk, dreq, skb)) + goto drop; + child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); if (child == NULL) goto listen_overflow; - /* FIXME: deal with options */ - inet_csk_reqsk_queue_unlink(sk, req, prev); inet_csk_reqsk_queue_removed(sk, req); inet_csk_reqsk_queue_add(sk, req, child); @@ -245,7 +212,7 @@ listen_overflow: DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; drop: if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET) - req->rsk_ops->send_reset(skb); + req->rsk_ops->send_reset(sk, skb); inet_csk_reqsk_queue_drop(sk, req, prev); goto out; @@ -270,13 +237,13 @@ int dccp_child_process(struct sock *parent, struct sock *child, /* Wakeup parent, send SIGIO */ if (state == DCCP_RESPOND && child->sk_state != state) - parent->sk_data_ready(parent, 0); + parent->sk_data_ready(parent); } else { /* Alas, it is possible again, because we do lookup * in main socket hash table and lock on listening * socket does not protect us more. */ - sk_add_backlog(child, skb); + __sk_add_backlog(child, skb); } bh_unlock_sock(child); @@ -285,3 +252,27 @@ int dccp_child_process(struct sock *parent, struct sock *child, } EXPORT_SYMBOL_GPL(dccp_child_process); + +void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, + struct request_sock *rsk) +{ + DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state"); +} + +EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack); + +int dccp_reqsk_init(struct request_sock *req, + struct dccp_sock const *dp, struct sk_buff const *skb) +{ + struct dccp_request_sock *dreq = dccp_rsk(req); + + inet_rsk(req)->ir_rmt_port = dccp_hdr(skb)->dccph_sport; + inet_rsk(req)->ir_num = ntohs(dccp_hdr(skb)->dccph_dport); + inet_rsk(req)->acked = 0; + dreq->dreq_timestamp_echo = 0; + + /* inherit feature negotiation options from listening socket */ + return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg); +} + +EXPORT_SYMBOL_GPL(dccp_reqsk_init); diff --git a/net/dccp/options.c b/net/dccp/options.c index 0a76426c9ae..9bce31886bd 100644 --- a/net/dccp/options.c +++ b/net/dccp/options.c @@ -4,61 +4,54 @@ * An implementation of the DCCP protocol * Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> - * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> + * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/module.h> #include <linux/types.h> +#include <asm/unaligned.h> #include <linux/kernel.h> #include <linux/skbuff.h> #include "ackvec.h" #include "ccid.h" #include "dccp.h" +#include "feat.h" -/* stores the default values for new connection. may be changed with sysctl */ -static const struct dccp_options dccpo_default_values = { - .dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW, - .dccpo_rx_ccid = DCCPF_INITIAL_CCID, - .dccpo_tx_ccid = DCCPF_INITIAL_CCID, - .dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR, - .dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT, -}; - -void dccp_options_init(struct dccp_options *dccpo) -{ - memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo)); -} - -static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len) +u64 dccp_decode_value_var(const u8 *bf, const u8 len) { - u32 value = 0; + u64 value = 0; + if (len >= DCCP_OPTVAL_MAXLEN) + value += ((u64)*bf++) << 40; + if (len > 4) + value += ((u64)*bf++) << 32; if (len > 3) - value += *bf++ << 24; + value += ((u64)*bf++) << 24; if (len > 2) - value += *bf++ << 16; + value += ((u64)*bf++) << 16; if (len > 1) - value += *bf++ << 8; + value += ((u64)*bf++) << 8; if (len > 0) value += *bf; return value; } -int dccp_parse_options(struct sock *sk, struct sk_buff *skb) +/** + * dccp_parse_options - Parse DCCP options present in @skb + * @sk: client|server|listening dccp socket (when @dreq != NULL) + * @dreq: request socket to use during connection setup, or NULL + */ +int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, + struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); -#ifdef CONFIG_IP_DCCP_DEBUG - const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? - "CLIENT rx opt: " : "server rx opt: "; -#endif const struct dccp_hdr *dh = dccp_hdr(skb); const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type; unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); @@ -67,11 +60,15 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) (dh->dccph_doff * 4); struct dccp_options_received *opt_recv = &dp->dccps_options_received; unsigned char opt, len; - unsigned char *value; + unsigned char *uninitialized_var(value); u32 elapsed_time; + __be32 opt_val; + int rc; + int mandatory = 0; memset(opt_recv, 0, sizeof(*opt_recv)); + opt = len = 0; while (opt_ptr != opt_end) { opt = *opt_ptr++; len = 0; @@ -80,11 +77,11 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) /* Check if this isn't a single byte option */ if (opt > DCCPO_MAX_RESERVED) { if (opt_ptr == opt_end) - goto out_invalid_option; + goto out_nonsensical_length; len = *opt_ptr++; - if (len < 3) - goto out_invalid_option; + if (len < 2) + goto out_nonsensical_length; /* * Remove the type and len fields, leaving * just the value size @@ -94,134 +91,187 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) opt_ptr += len; if (opt_ptr > opt_end) - goto out_invalid_option; + goto out_nonsensical_length; } + /* + * CCID-specific options are ignored during connection setup, as + * negotiation may still be in progress (see RFC 4340, 10.3). + * The same applies to Ack Vectors, as these depend on the CCID. + */ + if (dreq != NULL && (opt >= DCCPO_MIN_RX_CCID_SPECIFIC || + opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1)) + goto ignore_option; + switch (opt) { case DCCPO_PADDING: break; + case DCCPO_MANDATORY: + if (mandatory) + goto out_invalid_option; + if (pkt_type != DCCP_PKT_DATA) + mandatory = 1; + break; case DCCPO_NDP_COUNT: - if (len > 3) + if (len > 6) goto out_invalid_option; opt_recv->dccpor_ndp = dccp_decode_value_var(value, len); - dccp_pr_debug("%sNDP count=%d\n", debug_prefix, - opt_recv->dccpor_ndp); + dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk), + (unsigned long long)opt_recv->dccpor_ndp); break; - case DCCPO_ACK_VECTOR_0: - case DCCPO_ACK_VECTOR_1: - if (pkt_type == DCCP_PKT_DATA) - continue; - - if (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_parse(sk, skb, opt, value, len)) + case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R: + if (pkt_type == DCCP_PKT_DATA) /* RFC 4340, 6 */ + break; + if (len == 0) goto out_invalid_option; + rc = dccp_feat_parse_options(sk, dreq, mandatory, opt, + *value, value + 1, len - 1); + if (rc) + goto out_featneg_failed; break; case DCCPO_TIMESTAMP: if (len != 4) goto out_invalid_option; - - opt_recv->dccpor_timestamp = ntohl(*(u32 *)value); - - dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp; - dccp_timestamp(sk, &dp->dccps_timestamp_time); - - dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n", - debug_prefix, opt_recv->dccpor_timestamp, + /* + * RFC 4340 13.1: "The precise time corresponding to + * Timestamp Value zero is not specified". We use + * zero to indicate absence of a meaningful timestamp. + */ + opt_val = get_unaligned((__be32 *)value); + if (unlikely(opt_val == 0)) { + DCCP_WARN("Timestamp with zero value\n"); + break; + } + + if (dreq != NULL) { + dreq->dreq_timestamp_echo = ntohl(opt_val); + dreq->dreq_timestamp_time = dccp_timestamp(); + } else { + opt_recv->dccpor_timestamp = + dp->dccps_timestamp_echo = ntohl(opt_val); + dp->dccps_timestamp_time = dccp_timestamp(); + } + dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", + dccp_role(sk), ntohl(opt_val), (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq); + /* schedule an Ack in case this sender is quiescent */ + inet_csk_schedule_ack(sk); break; case DCCPO_TIMESTAMP_ECHO: if (len != 4 && len != 6 && len != 8) goto out_invalid_option; - opt_recv->dccpor_timestamp_echo = ntohl(*(u32 *)value); + opt_val = get_unaligned((__be32 *)value); + opt_recv->dccpor_timestamp_echo = ntohl(opt_val); - dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ", - debug_prefix, + dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " + "ackno=%llu", dccp_role(sk), opt_recv->dccpor_timestamp_echo, len + 2, (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq); + value += 4; - if (len == 4) + if (len == 4) { /* no elapsed time included */ + dccp_pr_debug_cat("\n"); break; + } + + if (len == 6) { /* 2-byte elapsed time */ + __be16 opt_val2 = get_unaligned((__be16 *)value); + elapsed_time = ntohs(opt_val2); + } else { /* 4-byte elapsed time */ + opt_val = get_unaligned((__be32 *)value); + elapsed_time = ntohl(opt_val); + } - if (len == 6) - elapsed_time = ntohs(*(u16 *)(value + 4)); - else - elapsed_time = ntohl(*(u32 *)(value + 4)); + dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); /* Give precedence to the biggest ELAPSED_TIME */ if (elapsed_time > opt_recv->dccpor_elapsed_time) opt_recv->dccpor_elapsed_time = elapsed_time; break; case DCCPO_ELAPSED_TIME: - if (len != 2 && len != 4) - goto out_invalid_option; - - if (pkt_type == DCCP_PKT_DATA) - continue; + if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ + break; - if (len == 2) - elapsed_time = ntohs(*(u16 *)value); - else - elapsed_time = ntohl(*(u32 *)value); + if (len == 2) { + __be16 opt_val2 = get_unaligned((__be16 *)value); + elapsed_time = ntohs(opt_val2); + } else if (len == 4) { + opt_val = get_unaligned((__be32 *)value); + elapsed_time = ntohl(opt_val); + } else { + goto out_invalid_option; + } if (elapsed_time > opt_recv->dccpor_elapsed_time) opt_recv->dccpor_elapsed_time = elapsed_time; - dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix, - elapsed_time); + dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", + dccp_role(sk), elapsed_time); break; - /* - * From draft-ietf-dccp-spec-11.txt: - * - * Option numbers 128 through 191 are for - * options sent from the HC-Sender to the - * HC-Receiver; option numbers 192 through 255 - * are for options sent from the HC-Receiver to - * the HC-Sender. - */ - case 128 ... 191: { - const u16 idx = value - options; - + case DCCPO_MIN_RX_CCID_SPECIFIC ... DCCPO_MAX_RX_CCID_SPECIFIC: if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, - opt, len, idx, - value) != 0) + pkt_type, opt, value, len)) goto out_invalid_option; - } break; - case 192 ... 255: { - const u16 idx = value - options; - + case DCCPO_ACK_VECTOR_0: + case DCCPO_ACK_VECTOR_1: + if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ + break; + /* + * Ack vectors are processed by the TX CCID if it is + * interested. The RX CCID need not parse Ack Vectors, + * since it is only interested in clearing old state. + * Fall through. + */ + case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC: if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, - opt, len, idx, - value) != 0) + pkt_type, opt, value, len)) goto out_invalid_option; - } break; default: - pr_info("DCCP(%p): option %d(len=%d) not " - "implemented, ignoring\n", - sk, opt, len); + DCCP_CRIT("DCCP(%p): option %d(len=%d) not " + "implemented, ignoring", sk, opt, len); break; - } + } +ignore_option: + if (opt != DCCPO_MANDATORY) + mandatory = 0; } + /* mandatory was the last byte in option list -> reset connection */ + if (mandatory) + goto out_invalid_option; + +out_nonsensical_length: + /* RFC 4340, 5.8: ignore option and all remaining option space */ return 0; out_invalid_option: DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); - DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR; - pr_info("DCCP(%p): invalid option %d, len=%d\n", sk, opt, len); + rc = DCCP_RESET_CODE_OPTION_ERROR; +out_featneg_failed: + DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc); + DCCP_SKB_CB(skb)->dccpd_reset_code = rc; + DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt; + DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0; + DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0; return -1; } -static void dccp_encode_value_var(const u32 value, unsigned char *to, - const unsigned int len) +EXPORT_SYMBOL_GPL(dccp_parse_options); + +void dccp_encode_value_var(const u64 value, u8 *to, const u8 len) { + if (len >= DCCP_OPTVAL_MAXLEN) + *to++ = (value & 0xFF0000000000ull) >> 40; + if (len > 4) + *to++ = (value & 0xFF00000000ull) >> 32; if (len > 3) *to++ = (value & 0xFF000000) >> 24; if (len > 2) @@ -232,22 +282,20 @@ static void dccp_encode_value_var(const u32 value, unsigned char *to, *to++ = (value & 0xFF); } -static inline int dccp_ndp_len(const int ndp) +static inline u8 dccp_ndp_len(const u64 ndp) { - return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3; + if (likely(ndp <= 0xFF)) + return 1; + return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6); } -void dccp_insert_option(struct sock *sk, struct sk_buff *skb, - const unsigned char option, - const void *value, const unsigned char len) +int dccp_insert_option(struct sk_buff *skb, const unsigned char option, + const void *value, const unsigned char len) { unsigned char *to; - if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) { - LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert " - "%d option!\n", option); - return; - } + if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) + return -1; DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; @@ -256,14 +304,15 @@ void dccp_insert_option(struct sock *sk, struct sk_buff *skb, *to++ = len + 2; memcpy(to, value, len); + return 0; } EXPORT_SYMBOL_GPL(dccp_insert_option); -static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) +static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); - int ndp = dp->dccps_ndp_count; + u64 ndp = dp->dccps_ndp_count; if (dccp_non_data_packet(skb)) ++dp->dccps_ndp_count; @@ -276,7 +325,7 @@ static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) const int len = ndp_len + 2; if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) - return; + return -1; DCCP_SKB_CB(skb)->dccpd_opt_len += len; @@ -285,6 +334,8 @@ static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) *ptr++ = len; dccp_encode_value_var(ndp, ptr, ndp_len); } + + return 0; } static inline int dccp_elapsed_time_len(const u32 elapsed_time) @@ -292,171 +343,267 @@ static inline int dccp_elapsed_time_len(const u32 elapsed_time) return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; } -void dccp_insert_option_elapsed_time(struct sock *sk, - struct sk_buff *skb, - u32 elapsed_time) +static int dccp_insert_option_timestamp(struct sk_buff *skb) { -#ifdef CONFIG_IP_DCCP_DEBUG - struct dccp_sock *dp = dccp_sk(sk); - const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? - "CLIENT TX opt: " : "server TX opt: "; -#endif - const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); - const int len = 2 + elapsed_time_len; - unsigned char *to; + __be32 now = htonl(dccp_timestamp()); + /* yes this will overflow but that is the point as we want a + * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ - if (elapsed_time_len == 0) - return; + return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now)); +} + +static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, + struct dccp_request_sock *dreq, + struct sk_buff *skb) +{ + __be32 tstamp_echo; + unsigned char *to; + u32 elapsed_time, elapsed_time_len, len; - if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) { - LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to " - "insert elapsed time!\n"); - return; + if (dreq != NULL) { + elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; + tstamp_echo = htonl(dreq->dreq_timestamp_echo); + dreq->dreq_timestamp_echo = 0; + } else { + elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; + tstamp_echo = htonl(dp->dccps_timestamp_echo); + dp->dccps_timestamp_echo = 0; } + elapsed_time_len = dccp_elapsed_time_len(elapsed_time); + len = 6 + elapsed_time_len; + + if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) + return -1; + DCCP_SKB_CB(skb)->dccpd_opt_len += len; to = skb_push(skb, len); - *to++ = DCCPO_ELAPSED_TIME; + *to++ = DCCPO_TIMESTAMP_ECHO; *to++ = len; + memcpy(to, &tstamp_echo, 4); + to += 4; + if (elapsed_time_len == 2) { - const u16 var16 = htons((u16)elapsed_time); + const __be16 var16 = htons((u16)elapsed_time); memcpy(to, &var16, 2); - } else { - const u32 var32 = htonl(elapsed_time); + } else if (elapsed_time_len == 4) { + const __be32 var32 = htonl(elapsed_time); memcpy(to, &var32, 4); } - dccp_pr_debug("%sELAPSED_TIME=%u, len=%d, seqno=%llu\n", - debug_prefix, elapsed_time, - len, - (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); + return 0; } -EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); - -void dccp_timestamp(const struct sock *sk, struct timeval *tv) +static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb) { - const struct dccp_sock *dp = dccp_sk(sk); + struct dccp_sock *dp = dccp_sk(sk); + struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec; + struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); + const u16 buflen = dccp_ackvec_buflen(av); + /* Figure out how many options do we need to represent the ackvec */ + const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN); + u16 len = buflen + 2 * nr_opts; + u8 i, nonce = 0; + const unsigned char *tail, *from; + unsigned char *to; + + if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) { + DCCP_WARN("Lacking space for %u bytes on %s packet\n", len, + dccp_packet_name(dcb->dccpd_type)); + return -1; + } + /* + * Since Ack Vectors are variable-length, we can not always predict + * their size. To catch exception cases where the space is running out + * on the skb, a separate Sync is scheduled to carry the Ack Vector. + */ + if (len > DCCPAV_MIN_OPTLEN && + len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) { + DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), " + "MPS=%u ==> reduce payload size?\n", len, skb->len, + dcb->dccpd_opt_len, dp->dccps_mss_cache); + dp->dccps_sync_scheduled = 1; + return 0; + } + dcb->dccpd_opt_len += len; + + to = skb_push(skb, len); + len = buflen; + from = av->av_buf + av->av_buf_head; + tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN; + + for (i = 0; i < nr_opts; ++i) { + int copylen = len; - do_gettimeofday(tv); - tv->tv_sec -= dp->dccps_epoch.tv_sec; - tv->tv_usec -= dp->dccps_epoch.tv_usec; + if (len > DCCP_SINGLE_OPT_MAXLEN) + copylen = DCCP_SINGLE_OPT_MAXLEN; - while (tv->tv_usec < 0) { - tv->tv_sec--; - tv->tv_usec += USEC_PER_SEC; + /* + * RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via + * its type; ack_nonce is the sum of all individual buf_nonce's. + */ + nonce ^= av->av_buf_nonce[i]; + + *to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i]; + *to++ = copylen + 2; + + /* Check if buf_head wraps */ + if (from + copylen > tail) { + const u16 tailsize = tail - from; + + memcpy(to, from, tailsize); + to += tailsize; + len -= tailsize; + copylen -= tailsize; + from = av->av_buf; + } + + memcpy(to, from, copylen); + from += copylen; + to += copylen; + len -= copylen; } + /* + * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340. + */ + if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce)) + return -ENOBUFS; + return 0; } -EXPORT_SYMBOL_GPL(dccp_timestamp); - -void dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb) +/** + * dccp_insert_option_mandatory - Mandatory option (5.8.2) + * Note that since we are using skb_push, this function needs to be called + * _after_ inserting the option it is supposed to influence (stack order). + */ +int dccp_insert_option_mandatory(struct sk_buff *skb) { - struct timeval tv; - u32 now; - - dccp_timestamp(sk, &tv); - now = timeval_usecs(&tv) / 10; - /* yes this will overflow but that is the point as we want a - * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ + if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN) + return -1; - now = htonl(now); - dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now)); + DCCP_SKB_CB(skb)->dccpd_opt_len++; + *skb_push(skb, 1) = DCCPO_MANDATORY; + return 0; } -EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); - -static void dccp_insert_option_timestamp_echo(struct sock *sk, - struct sk_buff *skb) +/** + * dccp_insert_fn_opt - Insert single Feature-Negotiation option into @skb + * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R + * @feat: one out of %dccp_feature_numbers + * @val: NN value or SP array (preferred element first) to copy + * @len: true length of @val in bytes (excluding first element repetition) + * @repeat_first: whether to copy the first element of @val twice + * + * The last argument is used to construct Confirm options, where the preferred + * value and the preference list appear separately (RFC 4340, 6.3.1). Preference + * lists are kept such that the preferred entry is always first, so we only need + * to copy twice, and avoid the overhead of cloning into a bigger array. + */ +int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat, + u8 *val, u8 len, bool repeat_first) { - struct dccp_sock *dp = dccp_sk(sk); -#ifdef CONFIG_IP_DCCP_DEBUG - const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? - "CLIENT TX opt: " : "server TX opt: "; -#endif - struct timeval now; - u32 tstamp_echo; - u32 elapsed_time; - int len, elapsed_time_len; - unsigned char *to; - - dccp_timestamp(sk, &now); - elapsed_time = timeval_delta(&now, &dp->dccps_timestamp_time) / 10; - elapsed_time_len = dccp_elapsed_time_len(elapsed_time); - len = 6 + elapsed_time_len; + u8 tot_len, *to; - if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) { - LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert " - "timestamp echo!\n"); - return; + /* take the `Feature' field and possible repetition into account */ + if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) { + DCCP_WARN("length %u for feature %u too large\n", len, feat); + return -1; } - DCCP_SKB_CB(skb)->dccpd_opt_len += len; + if (unlikely(val == NULL || len == 0)) + len = repeat_first = false; + tot_len = 3 + repeat_first + len; - to = skb_push(skb, len); - *to++ = DCCPO_TIMESTAMP_ECHO; - *to++ = len; - - tstamp_echo = htonl(dp->dccps_timestamp_echo); - memcpy(to, &tstamp_echo, 4); - to += 4; - - if (elapsed_time_len == 2) { - const u16 var16 = htons((u16)elapsed_time); - memcpy(to, &var16, 2); - } else if (elapsed_time_len == 4) { - const u32 var32 = htonl(elapsed_time); - memcpy(to, &var32, 4); + if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) { + DCCP_WARN("packet too small for feature %d option!\n", feat); + return -1; } + DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len; + + to = skb_push(skb, tot_len); + *to++ = type; + *to++ = tot_len; + *to++ = feat; - dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, seqno=%llu\n", - debug_prefix, dp->dccps_timestamp_echo, - len, - (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); + if (repeat_first) + *to++ = *val; + if (len) + memcpy(to, val, len); + return 0; +} + +/* The length of all options needs to be a multiple of 4 (5.8) */ +static void dccp_insert_option_padding(struct sk_buff *skb) +{ + int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; - dp->dccps_timestamp_echo = 0; - dp->dccps_timestamp_time.tv_sec = 0; - dp->dccps_timestamp_time.tv_usec = 0; + if (padding != 0) { + padding = 4 - padding; + memset(skb_push(skb, padding), 0, padding); + DCCP_SKB_CB(skb)->dccpd_opt_len += padding; + } } -void dccp_insert_options(struct sock *sk, struct sk_buff *skb) +int dccp_insert_options(struct sock *sk, struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); DCCP_SKB_CB(skb)->dccpd_opt_len = 0; - if (dp->dccps_options.dccpo_send_ndp_count) - dccp_insert_option_ndp(sk, skb); + if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb)) + return -1; + + if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) { - if (!dccp_packet_without_ack(skb)) { - if (dp->dccps_options.dccpo_send_ack_vector && - dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) - dccp_insert_option_ackvec(sk, skb); - if (dp->dccps_timestamp_echo != 0) - dccp_insert_option_timestamp_echo(sk, skb); + /* Feature Negotiation */ + if (dccp_feat_insert_opts(dp, NULL, skb)) + return -1; + + if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) { + /* + * Obtain RTT sample from Request/Response exchange. + * This is currently used for TFRC initialisation. + */ + if (dccp_insert_option_timestamp(skb)) + return -1; + + } else if (dccp_ackvec_pending(sk) && + dccp_insert_option_ackvec(sk, skb)) { + return -1; + } } if (dp->dccps_hc_rx_insert_options) { - ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb); + if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) + return -1; dp->dccps_hc_rx_insert_options = 0; } - if (dp->dccps_hc_tx_insert_options) { - ccid_hc_tx_insert_options(dp->dccps_hc_tx_ccid, sk, skb); - dp->dccps_hc_tx_insert_options = 0; - } - /* XXX: insert other options when appropriate */ + if (dp->dccps_timestamp_echo != 0 && + dccp_insert_option_timestamp_echo(dp, NULL, skb)) + return -1; - if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) { - /* The length of all options has to be a multiple of 4 */ - int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; + dccp_insert_option_padding(skb); + return 0; +} - if (padding != 0) { - padding = 4 - padding; - memset(skb_push(skb, padding), 0, padding); - DCCP_SKB_CB(skb)->dccpd_opt_len += padding; - } - } +int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) +{ + DCCP_SKB_CB(skb)->dccpd_opt_len = 0; + + if (dccp_feat_insert_opts(NULL, dreq, skb)) + return -1; + + /* Obtain RTT sample from Response/Ack exchange (used by TFRC). */ + if (dccp_insert_option_timestamp(skb)) + return -1; + + if (dreq->dreq_timestamp_echo != 0 && + dccp_insert_option_timestamp_echo(NULL, dreq, skb)) + return -1; + + dccp_insert_option_padding(skb); + return 0; } diff --git a/net/dccp/output.c b/net/dccp/output.c index efd7ffb903a..0248e8a3460 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -1,6 +1,6 @@ /* * net/dccp/output.c - * + * * An implementation of the DCCP protocol * Arnaldo Carvalho de Melo <acme@conectiva.com.br> * @@ -10,10 +10,10 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/kernel.h> #include <linux/skbuff.h> +#include <linux/slab.h> #include <net/inet_sock.h> #include <net/sock.h> @@ -27,11 +27,13 @@ static inline void dccp_event_ack_sent(struct sock *sk) inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); } -static inline void dccp_skb_entail(struct sock *sk, struct sk_buff *skb) +/* enqueue @skb on sk_send_head for retransmission, return clone to send now */ +static struct sk_buff *dccp_skb_entail(struct sock *sk, struct sk_buff *skb) { skb_set_owner_w(skb, sk); WARN_ON(sk->sk_send_head); sk->sk_send_head = skb; + return skb_clone(sk->sk_send_head, gfp_any()); } /* @@ -43,58 +45,72 @@ static inline void dccp_skb_entail(struct sock *sk, struct sk_buff *skb) static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) { if (likely(skb != NULL)) { - const struct inet_sock *inet = inet_sk(sk); + struct inet_sock *inet = inet_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); struct dccp_sock *dp = dccp_sk(sk); struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); struct dccp_hdr *dh; /* XXX For now we're using only 48 bits sequence numbers */ - const int dccp_header_size = sizeof(*dh) + + const u32 dccp_header_size = sizeof(*dh) + sizeof(struct dccp_hdr_ext) + dccp_packet_hdr_len(dcb->dccpd_type); int err, set_ack = 1; u64 ackno = dp->dccps_gsr; - - dccp_inc_seqno(&dp->dccps_gss); + /* + * Increment GSS here already in case the option code needs it. + * Update GSS for real only if option processing below succeeds. + */ + dcb->dccpd_seq = ADD48(dp->dccps_gss, 1); switch (dcb->dccpd_type) { case DCCP_PKT_DATA: set_ack = 0; /* fall through */ case DCCP_PKT_DATAACK: + case DCCP_PKT_RESET: break; + case DCCP_PKT_REQUEST: + set_ack = 0; + /* Use ISS on the first (non-retransmitted) Request. */ + if (icsk->icsk_retransmits == 0) + dcb->dccpd_seq = dp->dccps_iss; + /* fall through */ + case DCCP_PKT_SYNC: case DCCP_PKT_SYNCACK: - ackno = dcb->dccpd_seq; + ackno = dcb->dccpd_ack_seq; /* fall through */ default: /* - * Only data packets should come through with skb->sk - * set. + * Set owner/destructor: some skbs are allocated via + * alloc_skb (e.g. when retransmission may happen). + * Only Data, DataAck, and Reset packets should come + * through here with skb->sk set. */ WARN_ON(skb->sk); skb_set_owner_w(skb, sk); break; } - dcb->dccpd_seq = dp->dccps_gss; - dccp_insert_options(sk, skb); - - skb->h.raw = skb_push(skb, dccp_header_size); - dh = dccp_hdr(skb); + if (dccp_insert_options(sk, skb)) { + kfree_skb(skb); + return -EPROTO; + } + /* Build DCCP header and checksum it. */ - memset(dh, 0, dccp_header_size); + dh = dccp_zeroed_hdr(skb, dccp_header_size); dh->dccph_type = dcb->dccpd_type; - dh->dccph_sport = inet->sport; - dh->dccph_dport = inet->dport; + dh->dccph_sport = inet->inet_sport; + dh->dccph_dport = inet->inet_dport; dh->dccph_doff = (dccp_header_size + dcb->dccpd_opt_len) / 4; dh->dccph_ccval = dcb->dccpd_ccval; + dh->dccph_cscov = dp->dccps_pcslen; /* XXX For now we're using only 48 bits sequence numbers */ dh->dccph_x = 1; - dp->dccps_awh = dp->dccps_gss; + dccp_update_gss(sk, dcb->dccpd_seq); dccp_hdr_set_seq(dh, dp->dccps_gss); if (set_ack) dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno); @@ -103,6 +119,11 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) case DCCP_PKT_REQUEST: dccp_hdr_request(skb)->dccph_req_service = dp->dccps_service; + /* + * Limit Ack window to ISS <= P.ackno <= GSS, so that + * only Responses to Requests we sent are considered. + */ + dp->dccps_awl = dp->dccps_iss; break; case DCCP_PKT_RESET: dccp_hdr_reset(skb)->dccph_reset_code = @@ -110,164 +131,263 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) break; } - icsk->icsk_af_ops->send_check(sk, skb->len, skb); + icsk->icsk_af_ops->send_check(sk, skb); if (set_ack) dccp_event_ack_sent(sk); DCCP_INC_STATS(DCCP_MIB_OUTSEGS); - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); - err = icsk->icsk_af_ops->queue_xmit(skb, 0); - if (err <= 0) - return err; - - /* NET_XMIT_CN is special. It does not guarantee, - * that this packet is lost. It tells that device - * is about to start to drop packets or already - * drops some packets of the same priority and - * invokes us to send less aggressively. - */ - return err == NET_XMIT_CN ? 0 : err; + err = icsk->icsk_af_ops->queue_xmit(sk, skb, &inet->cork.fl); + return net_xmit_eval(err); } return -ENOBUFS; } +/** + * dccp_determine_ccmps - Find out about CCID-specific packet-size limits + * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.), + * since the RX CCID is restricted to feedback packets (Acks), which are small + * in comparison with the data traffic. A value of 0 means "no current CCMPS". + */ +static u32 dccp_determine_ccmps(const struct dccp_sock *dp) +{ + const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid; + + if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL) + return 0; + return tx_ccid->ccid_ops->ccid_ccmps; +} + unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu) { struct inet_connection_sock *icsk = inet_csk(sk); struct dccp_sock *dp = dccp_sk(sk); - int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len - - sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext)); + u32 ccmps = dccp_determine_ccmps(dp); + u32 cur_mps = ccmps ? min(pmtu, ccmps) : pmtu; - /* Now subtract optional transport overhead */ - mss_now -= icsk->icsk_ext_hdr_len; + /* Account for header lengths and IPv4/v6 option overhead */ + cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len + + sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext)); /* - * FIXME: this should come from the CCID infrastructure, where, say, - * TFRC will say it wants TIMESTAMPS, ELAPSED time, etc, for now lets - * put a rough estimate for NDP + TIMESTAMP + TIMESTAMP_ECHO + ELAPSED - * TIME + TFRC_OPT_LOSS_EVENT_RATE + TFRC_OPT_RECEIVE_RATE + padding to - * make it a multiple of 4 + * Leave enough headroom for common DCCP header options. + * This only considers options which may appear on DCCP-Data packets, as + * per table 3 in RFC 4340, 5.8. When running out of space for other + * options (eg. Ack Vector which can take up to 255 bytes), it is better + * to schedule a separate Ack. Thus we leave headroom for the following: + * - 1 byte for Slow Receiver (11.6) + * - 6 bytes for Timestamp (13.1) + * - 10 bytes for Timestamp Echo (13.3) + * - 8 bytes for NDP count (7.7, when activated) + * - 6 bytes for Data Checksum (9.3) + * - %DCCPAV_MIN_OPTLEN bytes for Ack Vector size (11.4, when enabled) */ - - mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4; + cur_mps -= roundup(1 + 6 + 10 + dp->dccps_send_ndp_count * 8 + 6 + + (dp->dccps_hc_rx_ackvec ? DCCPAV_MIN_OPTLEN : 0), 4); /* And store cached results */ icsk->icsk_pmtu_cookie = pmtu; - dp->dccps_mss_cache = mss_now; + dp->dccps_mss_cache = cur_mps; - return mss_now; + return cur_mps; } EXPORT_SYMBOL_GPL(dccp_sync_mss); void dccp_write_space(struct sock *sk) { - read_lock(&sk->sk_callback_lock); + struct socket_wq *wq; - if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) - wake_up_interruptible(sk->sk_sleep); + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + if (wq_has_sleeper(wq)) + wake_up_interruptible(&wq->wait); /* Should agree with poll, otherwise some programs break */ if (sock_writeable(sk)) - sk_wake_async(sk, 2, POLL_OUT); + sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); - read_unlock(&sk->sk_callback_lock); + rcu_read_unlock(); } /** - * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet - * @sk: socket to wait for - * @timeo: for how long + * dccp_wait_for_ccid - Await CCID send permission + * @sk: socket to wait for + * @delay: timeout in jiffies + * + * This is used by CCIDs which need to delay the send time in process context. */ -static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb, - long *timeo) +static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay) { - struct dccp_sock *dp = dccp_sk(sk); DEFINE_WAIT(wait); - long delay; - int rc; - - while (1) { - prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); - - if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) - goto do_error; - if (!*timeo) - goto do_nonblock; - if (signal_pending(current)) - goto do_interrupted; - - rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb, - skb->len); - if (rc <= 0) - break; - delay = msecs_to_jiffies(rc); - if (delay > *timeo || delay < 0) - goto do_nonblock; - - sk->sk_write_pending++; - release_sock(sk); - *timeo -= schedule_timeout(delay); - lock_sock(sk); - sk->sk_write_pending--; + long remaining; + + prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); + sk->sk_write_pending++; + release_sock(sk); + + remaining = schedule_timeout(delay); + + lock_sock(sk); + sk->sk_write_pending--; + finish_wait(sk_sleep(sk), &wait); + + if (signal_pending(current) || sk->sk_err) + return -1; + return remaining; +} + +/** + * dccp_xmit_packet - Send data packet under control of CCID + * Transmits next-queued payload and informs CCID to account for the packet. + */ +static void dccp_xmit_packet(struct sock *sk) +{ + int err, len; + struct dccp_sock *dp = dccp_sk(sk); + struct sk_buff *skb = dccp_qpolicy_pop(sk); + + if (unlikely(skb == NULL)) + return; + len = skb->len; + + if (sk->sk_state == DCCP_PARTOPEN) { + const u32 cur_mps = dp->dccps_mss_cache - DCCP_FEATNEG_OVERHEAD; + /* + * See 8.1.5 - Handshake Completion. + * + * For robustness we resend Confirm options until the client has + * entered OPEN. During the initial feature negotiation, the MPS + * is smaller than usual, reduced by the Change/Confirm options. + */ + if (!list_empty(&dp->dccps_featneg) && len > cur_mps) { + DCCP_WARN("Payload too large (%d) for featneg.\n", len); + dccp_send_ack(sk); + dccp_feat_list_purge(&dp->dccps_featneg); + } + + inet_csk_schedule_ack(sk); + inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, + inet_csk(sk)->icsk_rto, + DCCP_RTO_MAX); + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; + } else if (dccp_ack_pending(sk)) { + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK; + } else { + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATA; } -out: - finish_wait(sk->sk_sleep, &wait); - return rc; - -do_error: - rc = -EPIPE; - goto out; -do_nonblock: - rc = -EAGAIN; - goto out; -do_interrupted: - rc = sock_intr_errno(*timeo); - goto out; + + err = dccp_transmit_skb(sk, skb); + if (err) + dccp_pr_debug("transmit_skb() returned err=%d\n", err); + /* + * Register this one as sent even if an error occurred. To the remote + * end a local packet drop is indistinguishable from network loss, i.e. + * any local drop will eventually be reported via receiver feedback. + */ + ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, len); + + /* + * If the CCID needs to transfer additional header options out-of-band + * (e.g. Ack Vectors or feature-negotiation options), it activates this + * flag to schedule a Sync. The Sync will automatically incorporate all + * currently pending header options, thus clearing the backlog. + */ + if (dp->dccps_sync_scheduled) + dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); } -int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo) +/** + * dccp_flush_write_queue - Drain queue at end of connection + * Since dccp_sendmsg queues packets without waiting for them to be sent, it may + * happen that the TX queue is not empty at the end of a connection. We give the + * HC-sender CCID a grace period of up to @time_budget jiffies. If this function + * returns with a non-empty write queue, it will be purged later. + */ +void dccp_flush_write_queue(struct sock *sk, long *time_budget) { - const struct dccp_sock *dp = dccp_sk(sk); - int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb, - skb->len); + struct dccp_sock *dp = dccp_sk(sk); + struct sk_buff *skb; + long delay, rc; - if (err > 0) - err = dccp_wait_for_ccid(sk, skb, timeo); + while (*time_budget > 0 && (skb = skb_peek(&sk->sk_write_queue))) { + rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); - if (err == 0) { - struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); - const int len = skb->len; + switch (ccid_packet_dequeue_eval(rc)) { + case CCID_PACKET_WILL_DEQUEUE_LATER: + /* + * If the CCID determines when to send, the next sending + * time is unknown or the CCID may not even send again + * (e.g. remote host crashes or lost Ack packets). + */ + DCCP_WARN("CCID did not manage to send all packets\n"); + return; + case CCID_PACKET_DELAY: + delay = msecs_to_jiffies(rc); + if (delay > *time_budget) + return; + rc = dccp_wait_for_ccid(sk, delay); + if (rc < 0) + return; + *time_budget -= (delay - rc); + /* check again if we can send now */ + break; + case CCID_PACKET_SEND_AT_ONCE: + dccp_xmit_packet(sk); + break; + case CCID_PACKET_ERR: + skb_dequeue(&sk->sk_write_queue); + kfree_skb(skb); + dccp_pr_debug("packet discarded due to err=%ld\n", rc); + } + } +} - if (sk->sk_state == DCCP_PARTOPEN) { - /* See 8.1.5. Handshake Completion */ - inet_csk_schedule_ack(sk); - inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, - inet_csk(sk)->icsk_rto, - DCCP_RTO_MAX); - dcb->dccpd_type = DCCP_PKT_DATAACK; - } else if (dccp_ack_pending(sk)) - dcb->dccpd_type = DCCP_PKT_DATAACK; - else - dcb->dccpd_type = DCCP_PKT_DATA; - - err = dccp_transmit_skb(sk, skb); - ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len); - } else - kfree_skb(skb); - - return err; +void dccp_write_xmit(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct sk_buff *skb; + + while ((skb = dccp_qpolicy_top(sk))) { + int rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb); + + switch (ccid_packet_dequeue_eval(rc)) { + case CCID_PACKET_WILL_DEQUEUE_LATER: + return; + case CCID_PACKET_DELAY: + sk_reset_timer(sk, &dp->dccps_xmit_timer, + jiffies + msecs_to_jiffies(rc)); + return; + case CCID_PACKET_SEND_AT_ONCE: + dccp_xmit_packet(sk); + break; + case CCID_PACKET_ERR: + dccp_qpolicy_drop(sk, skb); + dccp_pr_debug("packet discarded due to err=%d\n", rc); + } + } } -int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb) +/** + * dccp_retransmit_skb - Retransmit Request, Close, or CloseReq packets + * There are only four retransmittable packet types in DCCP: + * - Request in client-REQUEST state (sec. 8.1.1), + * - CloseReq in server-CLOSEREQ state (sec. 8.3), + * - Close in node-CLOSING state (sec. 8.3), + * - Acks in client-PARTOPEN state (sec. 8.1.5, handled by dccp_delack_timer()). + * This function expects sk->sk_send_head to contain the original skb. + */ +int dccp_retransmit_skb(struct sock *sk) { + WARN_ON(sk->sk_send_head == NULL); + if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk) != 0) return -EHOSTUNREACH; /* Routing failure or similar. */ - return dccp_transmit_skb(sk, (skb_cloned(skb) ? - pskb_copy(skb, GFP_ATOMIC): - skb_clone(skb, GFP_ATOMIC))); + /* this count is used to distinguish original and retransmitted skb */ + inet_csk(sk)->icsk_retransmits++; + + return dccp_transmit_skb(sk, skb_clone(sk->sk_send_head, GFP_ATOMIC)); } struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, @@ -275,151 +395,171 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, { struct dccp_hdr *dh; struct dccp_request_sock *dreq; - const int dccp_header_size = sizeof(struct dccp_hdr) + + const u32 dccp_header_size = sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext) + sizeof(struct dccp_hdr_response); - struct sk_buff *skb = sock_wmalloc(sk, MAX_HEADER + DCCP_MAX_OPT_LEN + - dccp_header_size, 1, + struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC); if (skb == NULL) return NULL; /* Reserve space for headers. */ - skb_reserve(skb, MAX_HEADER + DCCP_MAX_OPT_LEN + dccp_header_size); + skb_reserve(skb, sk->sk_prot->max_header); - skb->dst = dst_clone(dst); - skb->csum = 0; + skb_dst_set(skb, dst_clone(dst)); dreq = dccp_rsk(req); + if (inet_rsk(req)->acked) /* increase GSS upon retransmission */ + dccp_inc_seqno(&dreq->dreq_gss); DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE; - DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss; - dccp_insert_options(sk, skb); + DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_gss; + + /* Resolve feature dependencies resulting from choice of CCID */ + if (dccp_feat_server_ccid_dependencies(dreq)) + goto response_failed; - skb->h.raw = skb_push(skb, dccp_header_size); + if (dccp_insert_options_rsk(dreq, skb)) + goto response_failed; - dh = dccp_hdr(skb); - memset(dh, 0, dccp_header_size); + /* Build and checksum header */ + dh = dccp_zeroed_hdr(skb, dccp_header_size); - dh->dccph_sport = inet_sk(sk)->sport; - dh->dccph_dport = inet_rsk(req)->rmt_port; + dh->dccph_sport = htons(inet_rsk(req)->ir_num); + dh->dccph_dport = inet_rsk(req)->ir_rmt_port; dh->dccph_doff = (dccp_header_size + DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; dh->dccph_type = DCCP_PKT_RESPONSE; dh->dccph_x = 1; - dccp_hdr_set_seq(dh, dreq->dreq_iss); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_isr); + dccp_hdr_set_seq(dh, dreq->dreq_gss); + dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dreq->dreq_gsr); dccp_hdr_response(skb)->dccph_resp_service = dreq->dreq_service; - dh->dccph_checksum = dccp_v4_checksum(skb, inet_rsk(req)->loc_addr, - inet_rsk(req)->rmt_addr); + dccp_csum_outgoing(skb); + /* We use `acked' to remember that a Response was already sent. */ + inet_rsk(req)->acked = 1; DCCP_INC_STATS(DCCP_MIB_OUTSEGS); return skb; +response_failed: + kfree_skb(skb); + return NULL; } EXPORT_SYMBOL_GPL(dccp_make_response); -struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst, - const enum dccp_reset_codes code) - +/* answer offending packet in @rcv_skb with Reset from control socket @ctl */ +struct sk_buff *dccp_ctl_make_reset(struct sock *sk, struct sk_buff *rcv_skb) { - struct dccp_hdr *dh; - struct dccp_sock *dp = dccp_sk(sk); - const int dccp_header_size = sizeof(struct dccp_hdr) + - sizeof(struct dccp_hdr_ext) + - sizeof(struct dccp_hdr_reset); - struct sk_buff *skb = sock_wmalloc(sk, MAX_HEADER + DCCP_MAX_OPT_LEN + - dccp_header_size, 1, - GFP_ATOMIC); + struct dccp_hdr *rxdh = dccp_hdr(rcv_skb), *dh; + struct dccp_skb_cb *dcb = DCCP_SKB_CB(rcv_skb); + const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) + + sizeof(struct dccp_hdr_ext) + + sizeof(struct dccp_hdr_reset); + struct dccp_hdr_reset *dhr; + struct sk_buff *skb; + + skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); if (skb == NULL) return NULL; - /* Reserve space for headers. */ - skb_reserve(skb, MAX_HEADER + DCCP_MAX_OPT_LEN + dccp_header_size); + skb_reserve(skb, sk->sk_prot->max_header); - skb->dst = dst_clone(dst); - skb->csum = 0; + /* Swap the send and the receive. */ + dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len); + dh->dccph_type = DCCP_PKT_RESET; + dh->dccph_sport = rxdh->dccph_dport; + dh->dccph_dport = rxdh->dccph_sport; + dh->dccph_doff = dccp_hdr_reset_len / 4; + dh->dccph_x = 1; - dccp_inc_seqno(&dp->dccps_gss); + dhr = dccp_hdr_reset(skb); + dhr->dccph_reset_code = dcb->dccpd_reset_code; + + switch (dcb->dccpd_reset_code) { + case DCCP_RESET_CODE_PACKET_ERROR: + dhr->dccph_reset_data[0] = rxdh->dccph_type; + break; + case DCCP_RESET_CODE_OPTION_ERROR: /* fall through */ + case DCCP_RESET_CODE_MANDATORY_ERROR: + memcpy(dhr->dccph_reset_data, dcb->dccpd_reset_data, 3); + break; + } + /* + * From RFC 4340, 8.3.1: + * If P.ackno exists, set R.seqno := P.ackno + 1. + * Else set R.seqno := 0. + */ + if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) + dccp_hdr_set_seq(dh, ADD48(dcb->dccpd_ack_seq, 1)); + dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dcb->dccpd_seq); - DCCP_SKB_CB(skb)->dccpd_reset_code = code; - DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; - DCCP_SKB_CB(skb)->dccpd_seq = dp->dccps_gss; - dccp_insert_options(sk, skb); + dccp_csum_outgoing(skb); + return skb; +} - skb->h.raw = skb_push(skb, dccp_header_size); +EXPORT_SYMBOL_GPL(dccp_ctl_make_reset); - dh = dccp_hdr(skb); - memset(dh, 0, dccp_header_size); +/* send Reset on established socket, to close or abort the connection */ +int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code) +{ + struct sk_buff *skb; + /* + * FIXME: what if rebuild_header fails? + * Should we be doing a rebuild_header here? + */ + int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk); - dh->dccph_sport = inet_sk(sk)->sport; - dh->dccph_dport = inet_sk(sk)->dport; - dh->dccph_doff = (dccp_header_size + - DCCP_SKB_CB(skb)->dccpd_opt_len) / 4; - dh->dccph_type = DCCP_PKT_RESET; - dh->dccph_x = 1; - dccp_hdr_set_seq(dh, dp->dccps_gss); - dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dp->dccps_gsr); + if (err != 0) + return err; - dccp_hdr_reset(skb)->dccph_reset_code = code; + skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC); + if (skb == NULL) + return -ENOBUFS; - dh->dccph_checksum = dccp_v4_checksum(skb, inet_sk(sk)->saddr, - inet_sk(sk)->daddr); + /* Reserve space for headers and prepare control bits. */ + skb_reserve(skb, sk->sk_prot->max_header); + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET; + DCCP_SKB_CB(skb)->dccpd_reset_code = code; - DCCP_INC_STATS(DCCP_MIB_OUTSEGS); - return skb; + return dccp_transmit_skb(sk, skb); } /* * Do all connect socket setups that can be done AF independent. */ -static inline void dccp_connect_init(struct sock *sk) +int dccp_connect(struct sock *sk) { + struct sk_buff *skb; struct dccp_sock *dp = dccp_sk(sk); struct dst_entry *dst = __sk_dst_get(sk); struct inet_connection_sock *icsk = inet_csk(sk); sk->sk_err = 0; sock_reset_flag(sk, SOCK_DONE); - - dccp_sync_mss(sk, dst_mtu(dst)); - dccp_update_gss(sk, dp->dccps_iss); - /* - * SWL and AWL are initially adjusted so that they are not less than - * the initial Sequence Numbers received and sent, respectively: - * SWL := max(GSR + 1 - floor(W/4), ISR), - * AWL := max(GSS - W' + 1, ISS). - * These adjustments MUST be applied only at the beginning of the - * connection. - */ - dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss)); - - icsk->icsk_retransmits = 0; -} + dccp_sync_mss(sk, dst_mtu(dst)); -int dccp_connect(struct sock *sk) -{ - struct sk_buff *skb; - struct inet_connection_sock *icsk = inet_csk(sk); + /* do not connect if feature negotiation setup fails */ + if (dccp_feat_finalise_settings(dccp_sk(sk))) + return -EPROTO; - dccp_connect_init(sk); + /* Initialise GAR as per 8.5; AWL/AWH are set in dccp_transmit_skb() */ + dp->dccps_gar = dp->dccps_iss; - skb = alloc_skb(MAX_DCCP_HEADER + 15, sk->sk_allocation); + skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation); if (unlikely(skb == NULL)) return -ENOBUFS; /* Reserve space for headers. */ - skb_reserve(skb, MAX_DCCP_HEADER); + skb_reserve(skb, sk->sk_prot->max_header); DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST; - skb->csum = 0; - dccp_skb_entail(sk, skb); - dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL)); + dccp_transmit_skb(sk, dccp_skb_entail(sk, skb)); DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS); /* Timer for repeating the REQUEST until an answer. */ + icsk->icsk_retransmits = 0; inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto, DCCP_RTO_MAX); return 0; @@ -431,7 +571,8 @@ void dccp_send_ack(struct sock *sk) { /* If we have been reset, we may not send again. */ if (sk->sk_state != DCCP_CLOSED) { - struct sk_buff *skb = alloc_skb(MAX_DCCP_HEADER, GFP_ATOMIC); + struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, + GFP_ATOMIC); if (skb == NULL) { inet_csk_schedule_ack(sk); @@ -443,8 +584,7 @@ void dccp_send_ack(struct sock *sk) } /* Reserve space for headers */ - skb_reserve(skb, MAX_DCCP_HEADER); - skb->csum = 0; + skb_reserve(skb, sk->sk_prot->max_header); DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_ACK; dccp_transmit_skb(sk, skb); } @@ -452,6 +592,8 @@ void dccp_send_ack(struct sock *sk) EXPORT_SYMBOL_GPL(dccp_send_ack); +#if 0 +/* FIXME: Is this still necessary (11.3) - currently nowhere used by DCCP. */ void dccp_send_delayed_ack(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); @@ -481,8 +623,9 @@ void dccp_send_delayed_ack(struct sock *sk) icsk->icsk_ack.timeout = timeout; sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout); } +#endif -void dccp_send_sync(struct sock *sk, const u64 seq, +void dccp_send_sync(struct sock *sk, const u64 ackno, const enum dccp_pkt_type pkt_type) { /* @@ -490,21 +633,30 @@ void dccp_send_sync(struct sock *sk, const u64 seq, * dccp_transmit_skb() will set the ownership to this * sock. */ - struct sk_buff *skb = alloc_skb(MAX_DCCP_HEADER, GFP_ATOMIC); + struct sk_buff *skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC); - if (skb == NULL) + if (skb == NULL) { /* FIXME: how to make sure the sync is sent? */ + DCCP_CRIT("could not send %s", dccp_packet_name(pkt_type)); return; + } /* Reserve space for headers and prepare control bits. */ - skb_reserve(skb, MAX_DCCP_HEADER); - skb->csum = 0; + skb_reserve(skb, sk->sk_prot->max_header); DCCP_SKB_CB(skb)->dccpd_type = pkt_type; - DCCP_SKB_CB(skb)->dccpd_seq = seq; + DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno; + + /* + * Clear the flag in case the Sync was scheduled for out-of-band data, + * such as carrying a long Ack Vector. + */ + dccp_sk(sk)->dccps_sync_scheduled = 0; dccp_transmit_skb(sk, skb); } +EXPORT_SYMBOL_GPL(dccp_send_sync); + /* * Send a DCCP_PKT_CLOSE/CLOSEREQ. The caller locks the socket for us. This * cannot be allowed to fail queueing a DCCP_PKT_CLOSE/CLOSEREQ frame under @@ -522,13 +674,25 @@ void dccp_send_close(struct sock *sk, const int active) /* Reserve space for headers and prepare control bits. */ skb_reserve(skb, sk->sk_prot->max_header); - skb->csum = 0; - DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ? - DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ; + if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait) + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ; + else + DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE; if (active) { - dccp_skb_entail(sk, skb); - dccp_transmit_skb(sk, skb_clone(skb, prio)); - } else - dccp_transmit_skb(sk, skb); + skb = dccp_skb_entail(sk, skb); + /* + * Retransmission timer for active-close: RFC 4340, 8.3 requires + * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ + * state can be left. The initial timeout is 2 RTTs. + * Since RTT measurement is done by the CCIDs, there is no easy + * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4 + * is too low (200ms); we use a high value to avoid unnecessary + * retransmissions when the link RTT is > 0.2 seconds. + * FIXME: Let main module sample RTTs and use that instead. + */ + inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, + DCCP_TIMEOUT_INIT, DCCP_RTO_MAX); + } + dccp_transmit_skb(sk, skb); } diff --git a/net/dccp/probe.c b/net/dccp/probe.c new file mode 100644 index 00000000000..595ddf0459d --- /dev/null +++ b/net/dccp/probe.c @@ -0,0 +1,203 @@ +/* + * dccp_probe - Observe the DCCP flow with kprobes. + * + * The idea for this came from Werner Almesberger's umlsim + * Copyright (C) 2004, Stephen Hemminger <shemminger@osdl.org> + * + * Modified for DCCP from Stephen Hemminger's code + * Copyright (C) 2006, Ian McDonald <ian.mcdonald@jandi.co.nz> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/kernel.h> +#include <linux/kprobes.h> +#include <linux/socket.h> +#include <linux/dccp.h> +#include <linux/proc_fs.h> +#include <linux/module.h> +#include <linux/kfifo.h> +#include <linux/vmalloc.h> +#include <linux/gfp.h> +#include <net/net_namespace.h> + +#include "dccp.h" +#include "ccid.h" +#include "ccids/ccid3.h" + +static int port; + +static int bufsize = 64 * 1024; + +static const char procname[] = "dccpprobe"; + +static struct { + struct kfifo fifo; + spinlock_t lock; + wait_queue_head_t wait; + struct timespec tstart; +} dccpw; + +static void printl(const char *fmt, ...) +{ + va_list args; + int len; + struct timespec now; + char tbuf[256]; + + va_start(args, fmt); + getnstimeofday(&now); + + now = timespec_sub(now, dccpw.tstart); + + len = sprintf(tbuf, "%lu.%06lu ", + (unsigned long) now.tv_sec, + (unsigned long) now.tv_nsec / NSEC_PER_USEC); + len += vscnprintf(tbuf+len, sizeof(tbuf)-len, fmt, args); + va_end(args); + + kfifo_in_locked(&dccpw.fifo, tbuf, len, &dccpw.lock); + wake_up(&dccpw.wait); +} + +static int jdccp_sendmsg(struct kiocb *iocb, struct sock *sk, + struct msghdr *msg, size_t size) +{ + const struct inet_sock *inet = inet_sk(sk); + struct ccid3_hc_tx_sock *hc = NULL; + + if (ccid_get_current_tx_ccid(dccp_sk(sk)) == DCCPC_CCID3) + hc = ccid3_hc_tx_sk(sk); + + if (port == 0 || ntohs(inet->inet_dport) == port || + ntohs(inet->inet_sport) == port) { + if (hc) + printl("%pI4:%u %pI4:%u %d %d %d %d %u %llu %llu %d\n", + &inet->inet_saddr, ntohs(inet->inet_sport), + &inet->inet_daddr, ntohs(inet->inet_dport), size, + hc->tx_s, hc->tx_rtt, hc->tx_p, + hc->tx_x_calc, hc->tx_x_recv >> 6, + hc->tx_x >> 6, hc->tx_t_ipi); + else + printl("%pI4:%u %pI4:%u %d\n", + &inet->inet_saddr, ntohs(inet->inet_sport), + &inet->inet_daddr, ntohs(inet->inet_dport), + size); + } + + jprobe_return(); + return 0; +} + +static struct jprobe dccp_send_probe = { + .kp = { + .symbol_name = "dccp_sendmsg", + }, + .entry = jdccp_sendmsg, +}; + +static int dccpprobe_open(struct inode *inode, struct file *file) +{ + kfifo_reset(&dccpw.fifo); + getnstimeofday(&dccpw.tstart); + return 0; +} + +static ssize_t dccpprobe_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + int error = 0, cnt = 0; + unsigned char *tbuf; + + if (!buf) + return -EINVAL; + + if (len == 0) + return 0; + + tbuf = vmalloc(len); + if (!tbuf) + return -ENOMEM; + + error = wait_event_interruptible(dccpw.wait, + kfifo_len(&dccpw.fifo) != 0); + if (error) + goto out_free; + + cnt = kfifo_out_locked(&dccpw.fifo, tbuf, len, &dccpw.lock); + error = copy_to_user(buf, tbuf, cnt) ? -EFAULT : 0; + +out_free: + vfree(tbuf); + + return error ? error : cnt; +} + +static const struct file_operations dccpprobe_fops = { + .owner = THIS_MODULE, + .open = dccpprobe_open, + .read = dccpprobe_read, + .llseek = noop_llseek, +}; + +static __init int dccpprobe_init(void) +{ + int ret = -ENOMEM; + + init_waitqueue_head(&dccpw.wait); + spin_lock_init(&dccpw.lock); + if (kfifo_alloc(&dccpw.fifo, bufsize, GFP_KERNEL)) + return ret; + if (!proc_create(procname, S_IRUSR, init_net.proc_net, &dccpprobe_fops)) + goto err0; + + ret = register_jprobe(&dccp_send_probe); + if (ret) { + ret = request_module("dccp"); + if (!ret) + ret = register_jprobe(&dccp_send_probe); + } + + if (ret) + goto err1; + + pr_info("DCCP watch registered (port=%d)\n", port); + return 0; +err1: + remove_proc_entry(procname, init_net.proc_net); +err0: + kfifo_free(&dccpw.fifo); + return ret; +} +module_init(dccpprobe_init); + +static __exit void dccpprobe_exit(void) +{ + kfifo_free(&dccpw.fifo); + remove_proc_entry(procname, init_net.proc_net); + unregister_jprobe(&dccp_send_probe); + +} +module_exit(dccpprobe_exit); + +MODULE_PARM_DESC(port, "Port to match (0=all)"); +module_param(port, int, 0); + +MODULE_PARM_DESC(bufsize, "Log buffer size (default 64k)"); +module_param(bufsize, int, 0); + +MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>"); +MODULE_DESCRIPTION("DCCP snooper"); +MODULE_LICENSE("GPL"); diff --git a/net/dccp/proto.c b/net/dccp/proto.c index 65b11ea90d8..de2c1e71930 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -9,7 +9,6 @@ * published by the Free Software Foundation. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/module.h> #include <linux/types.h> @@ -21,15 +20,14 @@ #include <linux/if_arp.h> #include <linux/init.h> #include <linux/random.h> +#include <linux/slab.h> #include <net/checksum.h> -#include <net/inet_common.h> #include <net/inet_sock.h> -#include <net/protocol.h> #include <net/sock.h> #include <net/xfrm.h> -#include <asm/semaphore.h> +#include <asm/ioctls.h> #include <linux/spinlock.h> #include <linux/timer.h> #include <linux/delay.h> @@ -37,24 +35,121 @@ #include "ccid.h" #include "dccp.h" +#include "feat.h" DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly; EXPORT_SYMBOL_GPL(dccp_statistics); -atomic_t dccp_orphan_count = ATOMIC_INIT(0); - +struct percpu_counter dccp_orphan_count; EXPORT_SYMBOL_GPL(dccp_orphan_count); -static struct net_protocol dccp_protocol = { - .handler = dccp_v4_rcv, - .err_handler = dccp_v4_err, - .no_policy = 1, -}; +struct inet_hashinfo dccp_hashinfo; +EXPORT_SYMBOL_GPL(dccp_hashinfo); + +/* the maximum queue length for tx in packets. 0 is no limit */ +int sysctl_dccp_tx_qlen __read_mostly = 5; + +#ifdef CONFIG_IP_DCCP_DEBUG +static const char *dccp_state_name(const int state) +{ + static const char *const dccp_state_names[] = { + [DCCP_OPEN] = "OPEN", + [DCCP_REQUESTING] = "REQUESTING", + [DCCP_PARTOPEN] = "PARTOPEN", + [DCCP_LISTEN] = "LISTEN", + [DCCP_RESPOND] = "RESPOND", + [DCCP_CLOSING] = "CLOSING", + [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ", + [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE", + [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ", + [DCCP_TIME_WAIT] = "TIME_WAIT", + [DCCP_CLOSED] = "CLOSED", + }; + + if (state >= DCCP_MAX_STATES) + return "INVALID STATE!"; + else + return dccp_state_names[state]; +} +#endif + +void dccp_set_state(struct sock *sk, const int state) +{ + const int oldstate = sk->sk_state; + + dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk, + dccp_state_name(oldstate), dccp_state_name(state)); + WARN_ON(state == oldstate); + + switch (state) { + case DCCP_OPEN: + if (oldstate != DCCP_OPEN) + DCCP_INC_STATS(DCCP_MIB_CURRESTAB); + /* Client retransmits all Confirm options until entering OPEN */ + if (oldstate == DCCP_PARTOPEN) + dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg); + break; + + case DCCP_CLOSED: + if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ || + oldstate == DCCP_CLOSING) + DCCP_INC_STATS(DCCP_MIB_ESTABRESETS); + + sk->sk_prot->unhash(sk); + if (inet_csk(sk)->icsk_bind_hash != NULL && + !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) + inet_put_port(sk); + /* fall through */ + default: + if (oldstate == DCCP_OPEN) + DCCP_DEC_STATS(DCCP_MIB_CURRESTAB); + } + + /* Change state AFTER socket is unhashed to avoid closed + * socket sitting in hash tables. + */ + sk->sk_state = state; +} + +EXPORT_SYMBOL_GPL(dccp_set_state); + +static void dccp_finish_passive_close(struct sock *sk) +{ + switch (sk->sk_state) { + case DCCP_PASSIVE_CLOSE: + /* Node (client or server) has received Close packet. */ + dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED); + dccp_set_state(sk, DCCP_CLOSED); + break; + case DCCP_PASSIVE_CLOSEREQ: + /* + * Client received CloseReq. We set the `active' flag so that + * dccp_send_close() retransmits the Close as per RFC 4340, 8.3. + */ + dccp_send_close(sk, 1); + dccp_set_state(sk, DCCP_CLOSING); + } +} + +void dccp_done(struct sock *sk) +{ + dccp_set_state(sk, DCCP_CLOSED); + dccp_clear_xmit_timers(sk); + + sk->sk_shutdown = SHUTDOWN_MASK; + + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + else + inet_csk_destroy_sock(sk); +} + +EXPORT_SYMBOL_GPL(dccp_done); const char *dccp_packet_name(const int type) { - static const char *dccp_packet_names[] = { + static const char *const dccp_packet_names[] = { [DCCP_PKT_REQUEST] = "REQUEST", [DCCP_PKT_RESPONSE] = "RESPONSE", [DCCP_PKT_DATA] = "DATA", @@ -75,39 +170,82 @@ const char *dccp_packet_name(const int type) EXPORT_SYMBOL_GPL(dccp_packet_name); -const char *dccp_state_name(const int state) -{ - static char *dccp_state_names[] = { - [DCCP_OPEN] = "OPEN", - [DCCP_REQUESTING] = "REQUESTING", - [DCCP_PARTOPEN] = "PARTOPEN", - [DCCP_LISTEN] = "LISTEN", - [DCCP_RESPOND] = "RESPOND", - [DCCP_CLOSING] = "CLOSING", - [DCCP_TIME_WAIT] = "TIME_WAIT", - [DCCP_CLOSED] = "CLOSED", - }; +int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct inet_connection_sock *icsk = inet_csk(sk); - if (state >= DCCP_MAX_STATES) - return "INVALID STATE!"; - else - return dccp_state_names[state]; + icsk->icsk_rto = DCCP_TIMEOUT_INIT; + icsk->icsk_syn_retries = sysctl_dccp_request_retries; + sk->sk_state = DCCP_CLOSED; + sk->sk_write_space = dccp_write_space; + icsk->icsk_sync_mss = dccp_sync_mss; + dp->dccps_mss_cache = 536; + dp->dccps_rate_last = jiffies; + dp->dccps_role = DCCP_ROLE_UNDEFINED; + dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT; + dp->dccps_tx_qlen = sysctl_dccp_tx_qlen; + + dccp_init_xmit_timers(sk); + + INIT_LIST_HEAD(&dp->dccps_featneg); + /* control socket doesn't need feat nego */ + if (likely(ctl_sock_initialized)) + return dccp_feat_init(sk); + return 0; } -EXPORT_SYMBOL_GPL(dccp_state_name); +EXPORT_SYMBOL_GPL(dccp_init_sock); -static inline int dccp_listen_start(struct sock *sk) +void dccp_destroy_sock(struct sock *sk) { struct dccp_sock *dp = dccp_sk(sk); - dp->dccps_role = DCCP_ROLE_LISTEN; /* - * Apps need to use setsockopt(DCCP_SOCKOPT_SERVICE) - * before calling listen() + * DCCP doesn't use sk_write_queue, just sk_send_head + * for retransmissions */ - if (dccp_service_not_initialized(sk)) + if (sk->sk_send_head != NULL) { + kfree_skb(sk->sk_send_head); + sk->sk_send_head = NULL; + } + + /* Clean up a referenced DCCP bind bucket. */ + if (inet_csk(sk)->icsk_bind_hash != NULL) + inet_put_port(sk); + + kfree(dp->dccps_service_list); + dp->dccps_service_list = NULL; + + if (dp->dccps_hc_rx_ackvec != NULL) { + dccp_ackvec_free(dp->dccps_hc_rx_ackvec); + dp->dccps_hc_rx_ackvec = NULL; + } + ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); + ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); + dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL; + + /* clean up feature negotiation state */ + dccp_feat_list_purge(&dp->dccps_featneg); +} + +EXPORT_SYMBOL_GPL(dccp_destroy_sock); + +static inline int dccp_listen_start(struct sock *sk, int backlog) +{ + struct dccp_sock *dp = dccp_sk(sk); + + dp->dccps_role = DCCP_ROLE_LISTEN; + /* do not start to listen if feature negotiation setup fails */ + if (dccp_feat_finalise_settings(dp)) return -EPROTO; - return inet_csk_listen_start(sk, TCP_SYNQ_HSIZE); + return inet_csk_listen_start(sk, backlog); +} + +static inline int dccp_need_reset(int state) +{ + return state != DCCP_CLOSED && state != DCCP_LISTEN && + state != DCCP_REQUESTING; } int dccp_disconnect(struct sock *sk, int flags) @@ -120,21 +258,28 @@ int dccp_disconnect(struct sock *sk, int flags) if (old_state != DCCP_CLOSED) dccp_set_state(sk, DCCP_CLOSED); - /* ABORT function of RFC793 */ + /* + * This corresponds to the ABORT function of RFC793, sec. 3.8 + * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted". + */ if (old_state == DCCP_LISTEN) { inet_csk_listen_stop(sk); - /* FIXME: do the active reset thing */ + } else if (dccp_need_reset(old_state)) { + dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); + sk->sk_err = ECONNRESET; } else if (old_state == DCCP_REQUESTING) sk->sk_err = ECONNRESET; dccp_clear_xmit_timers(sk); + __skb_queue_purge(&sk->sk_receive_queue); + __skb_queue_purge(&sk->sk_write_queue); if (sk->sk_send_head != NULL) { __kfree_skb(sk->sk_send_head); sk->sk_send_head = NULL; } - inet->dport = 0; + inet->inet_dport = 0; if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) inet_reset_saddr(sk); @@ -146,7 +291,7 @@ int dccp_disconnect(struct sock *sk, int flags) inet_csk_delack_init(sk); __sk_dst_reset(sk); - BUG_TRAP(!inet->num || icsk->icsk_bind_hash); + WARN_ON(inet->inet_num && !icsk->icsk_bind_hash); sk->sk_error_report(sk); return err; @@ -167,7 +312,7 @@ unsigned int dccp_poll(struct file *file, struct socket *sock, unsigned int mask; struct sock *sk = sock->sk; - poll_wait(file, sk->sk_sleep, wait); + sock_poll_wait(file, sk_sleep(sk), wait); if (sk->sk_state == DCCP_LISTEN) return inet_csk_listen_poll(sk); @@ -183,7 +328,7 @@ unsigned int dccp_poll(struct file *file, struct socket *sock, if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED) mask |= POLLHUP; if (sk->sk_shutdown & RCV_SHUTDOWN) - mask |= POLLIN | POLLRDNORM; + mask |= POLLIN | POLLRDNORM | POLLRDHUP; /* Connected? */ if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) { @@ -191,7 +336,7 @@ unsigned int dccp_poll(struct file *file, struct socket *sock, mask |= POLLIN | POLLRDNORM; if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { - if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) { + if (sk_stream_is_writeable(sk)) { mask |= POLLOUT | POLLWRNORM; } else { /* send SIGIO later */ set_bit(SOCK_ASYNC_NOSPACE, @@ -202,7 +347,7 @@ unsigned int dccp_poll(struct file *file, struct socket *sock, * wspace test but before the flags are set, * IO signal will be lost. */ - if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) + if (sk_stream_is_writeable(sk)) mask |= POLLOUT | POLLWRNORM; } } @@ -214,19 +359,47 @@ EXPORT_SYMBOL_GPL(dccp_poll); int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg) { - dccp_pr_debug("entry\n"); - return -ENOIOCTLCMD; + int rc = -ENOTCONN; + + lock_sock(sk); + + if (sk->sk_state == DCCP_LISTEN) + goto out; + + switch (cmd) { + case SIOCINQ: { + struct sk_buff *skb; + unsigned long amount = 0; + + skb = skb_peek(&sk->sk_receive_queue); + if (skb != NULL) { + /* + * We will only return the amount of this packet since + * that is all that will be read. + */ + amount = skb->len; + } + rc = put_user(amount, (int __user *)arg); + } + break; + default: + rc = -ENOIOCTLCMD; + break; + } +out: + release_sock(sk); + return rc; } EXPORT_SYMBOL_GPL(dccp_ioctl); -static int dccp_setsockopt_service(struct sock *sk, const u32 service, - char __user *optval, int optlen) +static int dccp_setsockopt_service(struct sock *sk, const __be32 service, + char __user *optval, unsigned int optlen) { struct dccp_sock *dp = dccp_sk(sk); struct dccp_service_list *sl = NULL; - if (service == DCCP_SERVICE_INVALID_VALUE || + if (service == DCCP_SERVICE_INVALID_VALUE || optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32)) return -EINVAL; @@ -255,19 +428,88 @@ static int dccp_setsockopt_service(struct sock *sk, const u32 service, return 0; } -int dccp_setsockopt(struct sock *sk, int level, int optname, - char __user *optval, int optlen) +static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx) { - struct dccp_sock *dp; - int err; - int val; + u8 *list, len; + int i, rc; - if (level != SOL_DCCP) - return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level, - optname, optval, - optlen); + if (cscov < 0 || cscov > 15) + return -EINVAL; + /* + * Populate a list of permissible values, in the range cscov...15. This + * is necessary since feature negotiation of single values only works if + * both sides incidentally choose the same value. Since the list starts + * lowest-value first, negotiation will pick the smallest shared value. + */ + if (cscov == 0) + return 0; + len = 16 - cscov; + + list = kmalloc(len, GFP_KERNEL); + if (list == NULL) + return -ENOBUFS; + + for (i = 0; i < len; i++) + list[i] = cscov++; + + rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len); + + if (rc == 0) { + if (rx) + dccp_sk(sk)->dccps_pcrlen = cscov; + else + dccp_sk(sk)->dccps_pcslen = cscov; + } + kfree(list); + return rc; +} - if (optlen < sizeof(int)) +static int dccp_setsockopt_ccid(struct sock *sk, int type, + char __user *optval, unsigned int optlen) +{ + u8 *val; + int rc = 0; + + if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS) + return -EINVAL; + + val = memdup_user(optval, optlen); + if (IS_ERR(val)) + return PTR_ERR(val); + + lock_sock(sk); + if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID) + rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen); + + if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID)) + rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen); + release_sock(sk); + + kfree(val); + return rc; +} + +static int do_dccp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct dccp_sock *dp = dccp_sk(sk); + int val, err = 0; + + switch (optname) { + case DCCP_SOCKOPT_PACKET_SIZE: + DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n"); + return 0; + case DCCP_SOCKOPT_CHANGE_L: + case DCCP_SOCKOPT_CHANGE_R: + DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n"); + return 0; + case DCCP_SOCKOPT_CCID: + case DCCP_SOCKOPT_RX_CCID: + case DCCP_SOCKOPT_TX_CCID: + return dccp_setsockopt_ccid(sk, optname, optval, optlen); + } + + if (optlen < (int)sizeof(int)) return -EINVAL; if (get_user(val, (int __user *)optval)) @@ -277,26 +519,69 @@ int dccp_setsockopt(struct sock *sk, int level, int optname, return dccp_setsockopt_service(sk, val, optval, optlen); lock_sock(sk); - dp = dccp_sk(sk); - err = 0; - switch (optname) { - case DCCP_SOCKOPT_PACKET_SIZE: - dp->dccps_packet_size = val; + case DCCP_SOCKOPT_SERVER_TIMEWAIT: + if (dp->dccps_role != DCCP_ROLE_SERVER) + err = -EOPNOTSUPP; + else + dp->dccps_server_timewait = (val != 0); + break; + case DCCP_SOCKOPT_SEND_CSCOV: + err = dccp_setsockopt_cscov(sk, val, false); + break; + case DCCP_SOCKOPT_RECV_CSCOV: + err = dccp_setsockopt_cscov(sk, val, true); + break; + case DCCP_SOCKOPT_QPOLICY_ID: + if (sk->sk_state != DCCP_CLOSED) + err = -EISCONN; + else if (val < 0 || val >= DCCPQ_POLICY_MAX) + err = -EINVAL; + else + dp->dccps_qpolicy = val; + break; + case DCCP_SOCKOPT_QPOLICY_TXQLEN: + if (val < 0) + err = -EINVAL; + else + dp->dccps_tx_qlen = val; break; default: err = -ENOPROTOOPT; break; } - release_sock(sk); + return err; } +int dccp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, unsigned int optlen) +{ + if (level != SOL_DCCP) + return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level, + optname, optval, + optlen); + return do_dccp_setsockopt(sk, level, optname, optval, optlen); +} + EXPORT_SYMBOL_GPL(dccp_setsockopt); +#ifdef CONFIG_COMPAT +int compat_dccp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, unsigned int optlen) +{ + if (level != SOL_DCCP) + return inet_csk_compat_setsockopt(sk, level, optname, + optval, optlen); + return do_dccp_setsockopt(sk, level, optname, optval, optlen); +} + +EXPORT_SYMBOL_GPL(compat_dccp_setsockopt); +#endif + static int dccp_getsockopt_service(struct sock *sk, int len, - u32 __user *optval, + __be32 __user *optval, int __user *optlen) { const struct dccp_sock *dp = dccp_sk(sk); @@ -304,9 +589,6 @@ static int dccp_getsockopt_service(struct sock *sk, int len, int err = -ENOENT, slen = 0, total_len = sizeof(u32); lock_sock(sk); - if (dccp_service_not_initialized(sk)) - goto out; - if ((sl = dp->dccps_service_list) != NULL) { slen = sl->dccpsl_nr * sizeof(u32); total_len += slen; @@ -326,32 +608,57 @@ out: return err; } -int dccp_getsockopt(struct sock *sk, int level, int optname, +static int do_dccp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { struct dccp_sock *dp; int val, len; - if (level != SOL_DCCP) - return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level, - optname, optval, - optlen); if (get_user(len, optlen)) return -EFAULT; - if (len < sizeof(int)) + if (len < (int)sizeof(int)) return -EINVAL; dp = dccp_sk(sk); switch (optname) { case DCCP_SOCKOPT_PACKET_SIZE: - val = dp->dccps_packet_size; - len = sizeof(dp->dccps_packet_size); - break; + DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n"); + return 0; case DCCP_SOCKOPT_SERVICE: return dccp_getsockopt_service(sk, len, - (u32 __user *)optval, optlen); + (__be32 __user *)optval, optlen); + case DCCP_SOCKOPT_GET_CUR_MPS: + val = dp->dccps_mss_cache; + break; + case DCCP_SOCKOPT_AVAILABLE_CCIDS: + return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen); + case DCCP_SOCKOPT_TX_CCID: + val = ccid_get_current_tx_ccid(dp); + if (val < 0) + return -ENOPROTOOPT; + break; + case DCCP_SOCKOPT_RX_CCID: + val = ccid_get_current_rx_ccid(dp); + if (val < 0) + return -ENOPROTOOPT; + break; + case DCCP_SOCKOPT_SERVER_TIMEWAIT: + val = dp->dccps_server_timewait; + break; + case DCCP_SOCKOPT_SEND_CSCOV: + val = dp->dccps_pcslen; + break; + case DCCP_SOCKOPT_RECV_CSCOV: + val = dp->dccps_pcrlen; + break; + case DCCP_SOCKOPT_QPOLICY_ID: + val = dp->dccps_qpolicy; + break; + case DCCP_SOCKOPT_QPOLICY_TXQLEN: + val = dp->dccps_tx_qlen; + break; case 128 ... 191: return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname, len, (u32 __user *)optval, optlen); @@ -362,14 +669,79 @@ int dccp_getsockopt(struct sock *sk, int level, int optname, return -ENOPROTOOPT; } + len = sizeof(val); if (put_user(len, optlen) || copy_to_user(optval, &val, len)) return -EFAULT; return 0; } +int dccp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen) +{ + if (level != SOL_DCCP) + return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level, + optname, optval, + optlen); + return do_dccp_getsockopt(sk, level, optname, optval, optlen); +} + EXPORT_SYMBOL_GPL(dccp_getsockopt); +#ifdef CONFIG_COMPAT +int compat_dccp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen) +{ + if (level != SOL_DCCP) + return inet_csk_compat_getsockopt(sk, level, optname, + optval, optlen); + return do_dccp_getsockopt(sk, level, optname, optval, optlen); +} + +EXPORT_SYMBOL_GPL(compat_dccp_getsockopt); +#endif + +static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb) +{ + struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg); + + /* + * Assign an (opaque) qpolicy priority value to skb->priority. + * + * We are overloading this skb field for use with the qpolicy subystem. + * The skb->priority is normally used for the SO_PRIORITY option, which + * is initialised from sk_priority. Since the assignment of sk_priority + * to skb->priority happens later (on layer 3), we overload this field + * for use with queueing priorities as long as the skb is on layer 4. + * The default priority value (if nothing is set) is 0. + */ + skb->priority = 0; + + for (; cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) { + + if (!CMSG_OK(msg, cmsg)) + return -EINVAL; + + if (cmsg->cmsg_level != SOL_DCCP) + continue; + + if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX && + !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type)) + return -EINVAL; + + switch (cmsg->cmsg_type) { + case DCCP_SCM_PRIORITY: + if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32))) + return -EINVAL; + skb->priority = *(__u32 *)CMSG_DATA(cmsg); + break; + default: + return -EINVAL; + } + } + return 0; +} + int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len) { @@ -384,6 +756,12 @@ int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, return -EMSGSIZE; lock_sock(sk); + + if (dccp_qpolicy_full(sk)) { + rc = -EAGAIN; + goto out_release; + } + timeo = sock_sndtimeo(sk, noblock); /* @@ -391,7 +769,7 @@ int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, * so that the trick in dccp_rcv_request_sent_state_process. */ /* Wait for a connection to finish. */ - if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN | DCCPF_CLOSING)) + if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN)) if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0) goto out_release; @@ -407,17 +785,18 @@ int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, if (rc != 0) goto out_discard; - rc = dccp_write_xmit(sk, skb, &timeo); + rc = dccp_msghdr_parse(msg, skb); + if (rc != 0) + goto out_discard; + + dccp_qpolicy_push(sk, skb); /* - * XXX we don't use sk_write_queue, so just discard the packet. - * Current plan however is to _use_ sk_write_queue with - * an algorith similar to tcp_sendmsg, where the main difference - * is that in DCCP we have to respect packet boundaries, so - * no coalescing of skbs. - * - * This bug was _quickly_ found & fixed by just looking at an OSTRA - * generated callgraph 8) -acme + * The xmit_timer is set if the TX CCID is rate-based and will expire + * when congestion control permits to release further packets into the + * network. Window-based CCIDs do not use this timer. */ + if (!timer_pending(&dp->dccps_xmit_timer)) + dccp_write_xmit(sk); out_release: release_sock(sk); return rc ? : len; @@ -451,19 +830,26 @@ int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, dh = dccp_hdr(skb); - if (dh->dccph_type == DCCP_PKT_DATA || - dh->dccph_type == DCCP_PKT_DATAACK) + switch (dh->dccph_type) { + case DCCP_PKT_DATA: + case DCCP_PKT_DATAACK: goto found_ok_skb; - if (dh->dccph_type == DCCP_PKT_RESET || - dh->dccph_type == DCCP_PKT_CLOSE) { - dccp_pr_debug("found fin ok!\n"); + case DCCP_PKT_CLOSE: + case DCCP_PKT_CLOSEREQ: + if (!(flags & MSG_PEEK)) + dccp_finish_passive_close(sk); + /* fall through */ + case DCCP_PKT_RESET: + dccp_pr_debug("found fin (%s) ok!\n", + dccp_packet_name(dh->dccph_type)); len = 0; goto found_fin_ok; + default: + dccp_pr_debug("packet_type=%s\n", + dccp_packet_name(dh->dccph_type)); + sk_eat_skb(sk, skb, false); } - dccp_pr_debug("packet_type=%s\n", - dccp_packet_name(dh->dccph_type)); - sk_eat_skb(sk, skb); verify_sock_status: if (sock_flag(sk, SOCK_DONE)) { len = 0; @@ -515,9 +901,11 @@ verify_sock_status: len = -EFAULT; break; } + if (flags & MSG_TRUNC) + len = skb->len; found_fin_ok: if (!(flags & MSG_PEEK)) - sk_eat_skb(sk, skb); + sk_eat_skb(sk, skb, false); break; } while (1); out: @@ -551,7 +939,7 @@ int inet_dccp_listen(struct socket *sock, int backlog) * FIXME: here it probably should be sk->sk_prot->listen_start * see tcp_listen_start */ - err = dccp_listen_start(sk); + err = dccp_listen_start(sk, backlog); if (err) goto out; } @@ -565,33 +953,39 @@ out: EXPORT_SYMBOL_GPL(inet_dccp_listen); -static const unsigned char dccp_new_state[] = { - /* current state: new state: action: */ - [0] = DCCP_CLOSED, - [DCCP_OPEN] = DCCP_CLOSING | DCCP_ACTION_FIN, - [DCCP_REQUESTING] = DCCP_CLOSED, - [DCCP_PARTOPEN] = DCCP_CLOSING | DCCP_ACTION_FIN, - [DCCP_LISTEN] = DCCP_CLOSED, - [DCCP_RESPOND] = DCCP_CLOSED, - [DCCP_CLOSING] = DCCP_CLOSED, - [DCCP_TIME_WAIT] = DCCP_CLOSED, - [DCCP_CLOSED] = DCCP_CLOSED, -}; - -static int dccp_close_state(struct sock *sk) +static void dccp_terminate_connection(struct sock *sk) { - const int next = dccp_new_state[sk->sk_state]; - const int ns = next & DCCP_STATE_MASK; + u8 next_state = DCCP_CLOSED; - if (ns != sk->sk_state) - dccp_set_state(sk, ns); + switch (sk->sk_state) { + case DCCP_PASSIVE_CLOSE: + case DCCP_PASSIVE_CLOSEREQ: + dccp_finish_passive_close(sk); + break; + case DCCP_PARTOPEN: + dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk); + inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK); + /* fall through */ + case DCCP_OPEN: + dccp_send_close(sk, 1); - return next & DCCP_ACTION_FIN; + if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER && + !dccp_sk(sk)->dccps_server_timewait) + next_state = DCCP_ACTIVE_CLOSEREQ; + else + next_state = DCCP_CLOSING; + /* fall through */ + default: + dccp_set_state(sk, next_state); + } } void dccp_close(struct sock *sk, long timeout) { + struct dccp_sock *dp = dccp_sk(sk); struct sk_buff *skb; + u32 data_was_unread = 0; + int state; lock_sock(sk); @@ -606,26 +1000,50 @@ void dccp_close(struct sock *sk, long timeout) goto adjudge_to_death; } + sk_stop_timer(sk, &dp->dccps_xmit_timer); + /* * We need to flush the recv. buffs. We do this only on the * descriptor close, not protocol-sourced closes, because the *reader process may not have drained the data yet! */ - /* FIXME: check for unread data */ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { + data_was_unread += skb->len; __kfree_skb(skb); } - if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { + if (data_was_unread) { + /* Unread data was tossed, send an appropriate Reset Code */ + DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread); + dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); + dccp_set_state(sk, DCCP_CLOSED); + } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { /* Check zero linger _after_ checking for unread data. */ sk->sk_prot->disconnect(sk, 0); - } else if (dccp_close_state(sk)) { - dccp_send_close(sk, 1); + } else if (sk->sk_state != DCCP_CLOSED) { + /* + * Normal connection termination. May need to wait if there are + * still packets in the TX queue that are delayed by the CCID. + */ + dccp_flush_write_queue(sk, &timeout); + dccp_terminate_connection(sk); } + /* + * Flush write queue. This may be necessary in several cases: + * - we have been closed by the peer but still have application data; + * - abortive termination (unread data or zero linger time), + * - normal termination but queue could not be flushed within time limit + */ + __skb_queue_purge(&sk->sk_write_queue); + sk_stream_wait_close(sk, timeout); adjudge_to_death: + state = sk->sk_state; + sock_hold(sk); + sock_orphan(sk); + /* * It is the last release_sock in its life. It will remove backlog. */ @@ -636,35 +1054,20 @@ adjudge_to_death: */ local_bh_disable(); bh_lock_sock(sk); - BUG_TRAP(!sock_owned_by_user(sk)); + WARN_ON(sock_owned_by_user(sk)); - sock_hold(sk); - sock_orphan(sk); + percpu_counter_inc(sk->sk_prot->orphan_count); - /* - * The last release_sock may have processed the CLOSE or RESET - * packet moving sock to CLOSED state, if not we have to fire - * the CLOSE/CLOSEREQ retransmission timer, see "8.3. Termination" - * in draft-ietf-dccp-spec-11. -acme - */ - if (sk->sk_state == DCCP_CLOSING) { - /* FIXME: should start at 2 * RTT */ - /* Timer for repeating the CLOSE/CLOSEREQ until an answer. */ - inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, - inet_csk(sk)->icsk_rto, - DCCP_RTO_MAX); -#if 0 - /* Yeah, we should use sk->sk_prot->orphan_count, etc */ - dccp_set_state(sk, DCCP_CLOSED); -#endif - } + /* Have we already been destroyed by a softirq or backlog? */ + if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED) + goto out; - atomic_inc(sk->sk_prot->orphan_count); if (sk->sk_state == DCCP_CLOSED) inet_csk_destroy_sock(sk); /* Otherwise, socket is reprieved until protocol close. */ +out: bh_unlock_sock(sk); local_bh_enable(); sock_put(sk); @@ -674,108 +1077,22 @@ EXPORT_SYMBOL_GPL(dccp_close); void dccp_shutdown(struct sock *sk, int how) { - dccp_pr_debug("entry\n"); + dccp_pr_debug("called shutdown(%x)\n", how); } EXPORT_SYMBOL_GPL(dccp_shutdown); -static const struct proto_ops inet_dccp_ops = { - .family = PF_INET, - .owner = THIS_MODULE, - .release = inet_release, - .bind = inet_bind, - .connect = inet_stream_connect, - .socketpair = sock_no_socketpair, - .accept = inet_accept, - .getname = inet_getname, - /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ - .poll = dccp_poll, - .ioctl = inet_ioctl, - /* FIXME: work on inet_listen to rename it to sock_common_listen */ - .listen = inet_dccp_listen, - .shutdown = inet_shutdown, - .setsockopt = sock_common_setsockopt, - .getsockopt = sock_common_getsockopt, - .sendmsg = inet_sendmsg, - .recvmsg = sock_common_recvmsg, - .mmap = sock_no_mmap, - .sendpage = sock_no_sendpage, -}; - -extern struct net_proto_family inet_family_ops; - -static struct inet_protosw dccp_v4_protosw = { - .type = SOCK_DCCP, - .protocol = IPPROTO_DCCP, - .prot = &dccp_prot, - .ops = &inet_dccp_ops, - .capability = -1, - .no_check = 0, - .flags = INET_PROTOSW_ICSK, -}; - -/* - * This is the global socket data structure used for responding to - * the Out-of-the-blue (OOTB) packets. A control sock will be created - * for this socket at the initialization time. - */ -struct socket *dccp_ctl_socket; - -static char dccp_ctl_socket_err_msg[] __initdata = - KERN_ERR "DCCP: Failed to create the control socket.\n"; - -static int __init dccp_ctl_sock_init(void) -{ - int rc = sock_create_kern(PF_INET, SOCK_DCCP, IPPROTO_DCCP, - &dccp_ctl_socket); - if (rc < 0) - printk(dccp_ctl_socket_err_msg); - else { - dccp_ctl_socket->sk->sk_allocation = GFP_ATOMIC; - inet_sk(dccp_ctl_socket->sk)->uc_ttl = -1; - - /* Unhash it so that IP input processing does not even - * see it, we do not wish this socket to see incoming - * packets. - */ - dccp_ctl_socket->sk->sk_prot->unhash(dccp_ctl_socket->sk); - } - - return rc; -} - -#ifdef CONFIG_IP_DCCP_UNLOAD_HACK -void dccp_ctl_sock_exit(void) +static inline int dccp_mib_init(void) { - if (dccp_ctl_socket != NULL) { - sock_release(dccp_ctl_socket); - dccp_ctl_socket = NULL; - } + dccp_statistics = alloc_percpu(struct dccp_mib); + if (!dccp_statistics) + return -ENOMEM; + return 0; } -EXPORT_SYMBOL_GPL(dccp_ctl_sock_exit); -#endif - -static int __init init_dccp_v4_mibs(void) +static inline void dccp_mib_exit(void) { - int rc = -ENOMEM; - - dccp_statistics[0] = alloc_percpu(struct dccp_mib); - if (dccp_statistics[0] == NULL) - goto out; - - dccp_statistics[1] = alloc_percpu(struct dccp_mib); - if (dccp_statistics[1] == NULL) - goto out_free_one; - - rc = 0; -out: - return rc; -out_free_one: - free_percpu(dccp_statistics[0]); - dccp_statistics[0] = NULL; - goto out; - + free_percpu(dccp_statistics); } static int thash_entries; @@ -783,8 +1100,8 @@ module_param(thash_entries, int, 0444); MODULE_PARM_DESC(thash_entries, "Number of ehash buckets"); #ifdef CONFIG_IP_DCCP_DEBUG -int dccp_debug; -module_param(dccp_debug, int, 0444); +bool dccp_debug; +module_param(dccp_debug, bool, 0644); MODULE_PARM_DESC(dccp_debug, "Enable debug messages"); EXPORT_SYMBOL_GPL(dccp_debug); @@ -794,17 +1111,21 @@ static int __init dccp_init(void) { unsigned long goal; int ehash_order, bhash_order, i; - int rc = proto_register(&dccp_prot, 1); + int rc; + BUILD_BUG_ON(sizeof(struct dccp_skb_cb) > + FIELD_SIZEOF(struct sk_buff, cb)); + rc = percpu_counter_init(&dccp_orphan_count, 0); if (rc) - goto out; - + goto out_fail; + rc = -ENOBUFS; + inet_hashinfo_init(&dccp_hashinfo); dccp_hashinfo.bind_bucket_cachep = kmem_cache_create("dccp_bind_bucket", sizeof(struct inet_bind_bucket), 0, - SLAB_HWCACHE_ALIGN, NULL, NULL); + SLAB_HWCACHE_ALIGN, NULL); if (!dccp_hashinfo.bind_bucket_cachep) - goto out_proto_unregister; + goto out_free_percpu; /* * Size and allocate the main established and bind bucket @@ -812,10 +1133,10 @@ static int __init dccp_init(void) * * The methodology is similar to that of the buffer cache. */ - if (num_physpages >= (128 * 1024)) - goal = num_physpages >> (21 - PAGE_SHIFT); + if (totalram_pages >= (128 * 1024)) + goal = totalram_pages >> (21 - PAGE_SHIFT); else - goal = num_physpages >> (23 - PAGE_SHIFT); + goal = totalram_pages >> (23 - PAGE_SHIFT); if (thash_entries) goal = (thash_entries * @@ -823,26 +1144,26 @@ static int __init dccp_init(void) for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++) ; do { - dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE / + unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE / sizeof(struct inet_ehash_bucket); - dccp_hashinfo.ehash_size >>= 1; - while (dccp_hashinfo.ehash_size & - (dccp_hashinfo.ehash_size - 1)) - dccp_hashinfo.ehash_size--; + + while (hash_size & (hash_size - 1)) + hash_size--; + dccp_hashinfo.ehash_mask = hash_size - 1; dccp_hashinfo.ehash = (struct inet_ehash_bucket *) - __get_free_pages(GFP_ATOMIC, ehash_order); + __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order); } while (!dccp_hashinfo.ehash && --ehash_order > 0); if (!dccp_hashinfo.ehash) { - printk(KERN_CRIT "Failed to allocate DCCP " - "established hash table\n"); + DCCP_CRIT("Failed to allocate DCCP established hash table"); goto out_free_bind_bucket_cachep; } - for (i = 0; i < (dccp_hashinfo.ehash_size << 1); i++) { - rwlock_init(&dccp_hashinfo.ehash[i].lock); - INIT_HLIST_HEAD(&dccp_hashinfo.ehash[i].chain); - } + for (i = 0; i <= dccp_hashinfo.ehash_mask; i++) + INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i); + + if (inet_ehash_locks_alloc(&dccp_hashinfo)) + goto out_free_dccp_ehash; bhash_order = ehash_order; @@ -853,12 +1174,12 @@ static int __init dccp_init(void) bhash_order > 0) continue; dccp_hashinfo.bhash = (struct inet_bind_hashbucket *) - __get_free_pages(GFP_ATOMIC, bhash_order); + __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, bhash_order); } while (!dccp_hashinfo.bhash && --bhash_order >= 0); if (!dccp_hashinfo.bhash) { - printk(KERN_CRIT "Failed to allocate DCCP bind hash table\n"); - goto out_free_dccp_ehash; + DCCP_CRIT("Failed to allocate DCCP bind hash table"); + goto out_free_dccp_locks; } for (i = 0; i < dccp_hashinfo.bhash_size; i++) { @@ -866,73 +1187,69 @@ static int __init dccp_init(void) INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain); } - if (init_dccp_v4_mibs()) + rc = dccp_mib_init(); + if (rc) goto out_free_dccp_bhash; - rc = -EAGAIN; - if (inet_add_protocol(&dccp_protocol, IPPROTO_DCCP)) - goto out_free_dccp_v4_mibs; + rc = dccp_ackvec_init(); + if (rc) + goto out_free_dccp_mib; - inet_register_protosw(&dccp_v4_protosw); + rc = dccp_sysctl_init(); + if (rc) + goto out_ackvec_exit; - rc = dccp_ctl_sock_init(); + rc = ccid_initialize_builtins(); if (rc) - goto out_unregister_protosw; -out: - return rc; -out_unregister_protosw: - inet_unregister_protosw(&dccp_v4_protosw); - inet_del_protocol(&dccp_protocol, IPPROTO_DCCP); -out_free_dccp_v4_mibs: - free_percpu(dccp_statistics[0]); - free_percpu(dccp_statistics[1]); - dccp_statistics[0] = dccp_statistics[1] = NULL; + goto out_sysctl_exit; + + dccp_timestamping_init(); + + return 0; + +out_sysctl_exit: + dccp_sysctl_exit(); +out_ackvec_exit: + dccp_ackvec_exit(); +out_free_dccp_mib: + dccp_mib_exit(); out_free_dccp_bhash: free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order); - dccp_hashinfo.bhash = NULL; +out_free_dccp_locks: + inet_ehash_locks_free(&dccp_hashinfo); out_free_dccp_ehash: free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order); - dccp_hashinfo.ehash = NULL; out_free_bind_bucket_cachep: kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); +out_free_percpu: + percpu_counter_destroy(&dccp_orphan_count); +out_fail: + dccp_hashinfo.bhash = NULL; + dccp_hashinfo.ehash = NULL; dccp_hashinfo.bind_bucket_cachep = NULL; -out_proto_unregister: - proto_unregister(&dccp_prot); - goto out; + return rc; } -static const char dccp_del_proto_err_msg[] __exitdata = - KERN_ERR "can't remove dccp net_protocol\n"; - static void __exit dccp_fini(void) { - inet_unregister_protosw(&dccp_v4_protosw); - - if (inet_del_protocol(&dccp_protocol, IPPROTO_DCCP) < 0) - printk(dccp_del_proto_err_msg); - - free_percpu(dccp_statistics[0]); - free_percpu(dccp_statistics[1]); + ccid_cleanup_builtins(); + dccp_mib_exit(); free_pages((unsigned long)dccp_hashinfo.bhash, get_order(dccp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket))); free_pages((unsigned long)dccp_hashinfo.ehash, - get_order(dccp_hashinfo.ehash_size * + get_order((dccp_hashinfo.ehash_mask + 1) * sizeof(struct inet_ehash_bucket))); + inet_ehash_locks_free(&dccp_hashinfo); kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep); - proto_unregister(&dccp_prot); + dccp_ackvec_exit(); + dccp_sysctl_exit(); + percpu_counter_destroy(&dccp_orphan_count); } module_init(dccp_init); module_exit(dccp_fini); -/* - * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) - * values directly, Also cover the case where the protocol is not specified, - * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP - */ -MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-33-type-6"); -MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-0-type-6"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>"); MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); diff --git a/net/dccp/qpolicy.c b/net/dccp/qpolicy.c new file mode 100644 index 00000000000..63c30bfa470 --- /dev/null +++ b/net/dccp/qpolicy.c @@ -0,0 +1,137 @@ +/* + * net/dccp/qpolicy.c + * + * Policy-based packet dequeueing interface for DCCP. + * + * Copyright (c) 2008 Tomasz Grobelny <tomasz@grobelny.oswiecenia.net> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License v2 + * as published by the Free Software Foundation. + */ +#include "dccp.h" + +/* + * Simple Dequeueing Policy: + * If tx_qlen is different from 0, enqueue up to tx_qlen elements. + */ +static void qpolicy_simple_push(struct sock *sk, struct sk_buff *skb) +{ + skb_queue_tail(&sk->sk_write_queue, skb); +} + +static bool qpolicy_simple_full(struct sock *sk) +{ + return dccp_sk(sk)->dccps_tx_qlen && + sk->sk_write_queue.qlen >= dccp_sk(sk)->dccps_tx_qlen; +} + +static struct sk_buff *qpolicy_simple_top(struct sock *sk) +{ + return skb_peek(&sk->sk_write_queue); +} + +/* + * Priority-based Dequeueing Policy: + * If tx_qlen is different from 0 and the queue has reached its upper bound + * of tx_qlen elements, replace older packets lowest-priority-first. + */ +static struct sk_buff *qpolicy_prio_best_skb(struct sock *sk) +{ + struct sk_buff *skb, *best = NULL; + + skb_queue_walk(&sk->sk_write_queue, skb) + if (best == NULL || skb->priority > best->priority) + best = skb; + return best; +} + +static struct sk_buff *qpolicy_prio_worst_skb(struct sock *sk) +{ + struct sk_buff *skb, *worst = NULL; + + skb_queue_walk(&sk->sk_write_queue, skb) + if (worst == NULL || skb->priority < worst->priority) + worst = skb; + return worst; +} + +static bool qpolicy_prio_full(struct sock *sk) +{ + if (qpolicy_simple_full(sk)) + dccp_qpolicy_drop(sk, qpolicy_prio_worst_skb(sk)); + return false; +} + +/** + * struct dccp_qpolicy_operations - TX Packet Dequeueing Interface + * @push: add a new @skb to the write queue + * @full: indicates that no more packets will be admitted + * @top: peeks at whatever the queueing policy defines as its `top' + */ +static struct dccp_qpolicy_operations { + void (*push) (struct sock *sk, struct sk_buff *skb); + bool (*full) (struct sock *sk); + struct sk_buff* (*top) (struct sock *sk); + __be32 params; + +} qpol_table[DCCPQ_POLICY_MAX] = { + [DCCPQ_POLICY_SIMPLE] = { + .push = qpolicy_simple_push, + .full = qpolicy_simple_full, + .top = qpolicy_simple_top, + .params = 0, + }, + [DCCPQ_POLICY_PRIO] = { + .push = qpolicy_simple_push, + .full = qpolicy_prio_full, + .top = qpolicy_prio_best_skb, + .params = DCCP_SCM_PRIORITY, + }, +}; + +/* + * Externally visible interface + */ +void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb) +{ + qpol_table[dccp_sk(sk)->dccps_qpolicy].push(sk, skb); +} + +bool dccp_qpolicy_full(struct sock *sk) +{ + return qpol_table[dccp_sk(sk)->dccps_qpolicy].full(sk); +} + +void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb) +{ + if (skb != NULL) { + skb_unlink(skb, &sk->sk_write_queue); + kfree_skb(skb); + } +} + +struct sk_buff *dccp_qpolicy_top(struct sock *sk) +{ + return qpol_table[dccp_sk(sk)->dccps_qpolicy].top(sk); +} + +struct sk_buff *dccp_qpolicy_pop(struct sock *sk) +{ + struct sk_buff *skb = dccp_qpolicy_top(sk); + + if (skb != NULL) { + /* Clear any skb fields that we used internally */ + skb->priority = 0; + skb_unlink(skb, &sk->sk_write_queue); + } + return skb; +} + +bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param) +{ + /* check if exactly one bit is set */ + if (!param || (param & (param - 1))) + return false; + return (qpol_table[dccp_sk(sk)->dccps_qpolicy].params & param) == param; +} diff --git a/net/dccp/sysctl.c b/net/dccp/sysctl.c new file mode 100644 index 00000000000..53731e45403 --- /dev/null +++ b/net/dccp/sysctl.c @@ -0,0 +1,118 @@ +/* + * net/dccp/sysctl.c + * + * An implementation of the DCCP protocol + * Arnaldo Carvalho de Melo <acme@mandriva.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License v2 + * as published by the Free Software Foundation. + */ + +#include <linux/mm.h> +#include <linux/sysctl.h> +#include "dccp.h" +#include "feat.h" + +#ifndef CONFIG_SYSCTL +#error This file should not be compiled without CONFIG_SYSCTL defined +#endif + +/* Boundary values */ +static int zero = 0, + one = 1, + u8_max = 0xFF; +static unsigned long seqw_min = DCCPF_SEQ_WMIN, + seqw_max = 0xFFFFFFFF; /* maximum on 32 bit */ + +static struct ctl_table dccp_default_table[] = { + { + .procname = "seq_window", + .data = &sysctl_dccp_sequence_window, + .maxlen = sizeof(sysctl_dccp_sequence_window), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &seqw_min, /* RFC 4340, 7.5.2 */ + .extra2 = &seqw_max, + }, + { + .procname = "rx_ccid", + .data = &sysctl_dccp_rx_ccid, + .maxlen = sizeof(sysctl_dccp_rx_ccid), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, /* RFC 4340, 10. */ + }, + { + .procname = "tx_ccid", + .data = &sysctl_dccp_tx_ccid, + .maxlen = sizeof(sysctl_dccp_tx_ccid), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, /* RFC 4340, 10. */ + }, + { + .procname = "request_retries", + .data = &sysctl_dccp_request_retries, + .maxlen = sizeof(sysctl_dccp_request_retries), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &one, + .extra2 = &u8_max, + }, + { + .procname = "retries1", + .data = &sysctl_dccp_retries1, + .maxlen = sizeof(sysctl_dccp_retries1), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, + }, + { + .procname = "retries2", + .data = &sysctl_dccp_retries2, + .maxlen = sizeof(sysctl_dccp_retries2), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, + }, + { + .procname = "tx_qlen", + .data = &sysctl_dccp_tx_qlen, + .maxlen = sizeof(sysctl_dccp_tx_qlen), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + }, + { + .procname = "sync_ratelimit", + .data = &sysctl_dccp_sync_ratelimit, + .maxlen = sizeof(sysctl_dccp_sync_ratelimit), + .mode = 0644, + .proc_handler = proc_dointvec_ms_jiffies, + }, + + { } +}; + +static struct ctl_table_header *dccp_table_header; + +int __init dccp_sysctl_init(void) +{ + dccp_table_header = register_net_sysctl(&init_net, "net/dccp/default", + dccp_default_table); + + return dccp_table_header != NULL ? 0 : -ENOMEM; +} + +void dccp_sysctl_exit(void) +{ + if (dccp_table_header != NULL) { + unregister_net_sysctl_table(dccp_table_header); + dccp_table_header = NULL; + } +} diff --git a/net/dccp/timer.c b/net/dccp/timer.c index aa34b576e22..1cd46a345cb 100644 --- a/net/dccp/timer.c +++ b/net/dccp/timer.c @@ -1,6 +1,6 @@ /* * net/dccp/timer.c - * + * * An implementation of the DCCP protocol * Arnaldo Carvalho de Melo <acme@conectiva.com.br> * @@ -10,28 +10,23 @@ * 2 of the License, or (at your option) any later version. */ -#include <linux/config.h> #include <linux/dccp.h> #include <linux/skbuff.h> +#include <linux/export.h> #include "dccp.h" -static void dccp_write_timer(unsigned long data); -static void dccp_keepalive_timer(unsigned long data); -static void dccp_delack_timer(unsigned long data); - -void dccp_init_xmit_timers(struct sock *sk) -{ - inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer, - &dccp_keepalive_timer); -} +/* sysctl variables governing numbers of retransmission attempts */ +int sysctl_dccp_request_retries __read_mostly = TCP_SYN_RETRIES; +int sysctl_dccp_retries1 __read_mostly = TCP_RETR1; +int sysctl_dccp_retries2 __read_mostly = TCP_RETR2; static void dccp_write_err(struct sock *sk) { sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT; sk->sk_error_report(sk); - dccp_v4_send_reset(sk, DCCP_RESET_CODE_ABORTED); + dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED); dccp_done(sk); DCCP_INC_STATS_BH(DCCP_MIB_ABORTONTIMEOUT); } @@ -44,12 +39,11 @@ static int dccp_write_timeout(struct sock *sk) if (sk->sk_state == DCCP_REQUESTING || sk->sk_state == DCCP_PARTOPEN) { if (icsk->icsk_retransmits != 0) - dst_negative_advice(&sk->sk_dst_cache); - retry_until = icsk->icsk_syn_retries ? : - /* FIXME! */ 3 /* FIXME! sysctl_tcp_syn_retries */; + dst_negative_advice(sk); + retry_until = icsk->icsk_syn_retries ? + : sysctl_dccp_request_retries; } else { - if (icsk->icsk_retransmits >= - /* FIXME! sysctl_tcp_retries1 */ 5 /* FIXME! */) { + if (icsk->icsk_retransmits >= sysctl_dccp_retries1) { /* NOTE. draft-ietf-tcpimpl-pmtud-01.txt requires pmtu black hole detection. :-( @@ -67,13 +61,13 @@ static int dccp_write_timeout(struct sock *sk) be far nicer to have all of the black holes fixed rather than fixing all of the TCP implementations." - Golden words :-). + Golden words :-). */ - dst_negative_advice(&sk->sk_dst_cache); + dst_negative_advice(sk); } - retry_until = /* FIXME! */ 15 /* FIXME! sysctl_tcp_retries2 */; + retry_until = sysctl_dccp_retries2; /* * FIXME: see tcp_write_timout and tcp_out_of_resources */ @@ -87,53 +81,6 @@ static int dccp_write_timeout(struct sock *sk) return 0; } -/* This is the same as tcp_delack_timer, sans prequeue & mem_reclaim stuff */ -static void dccp_delack_timer(unsigned long data) -{ - struct sock *sk = (struct sock *)data; - struct inet_connection_sock *icsk = inet_csk(sk); - - bh_lock_sock(sk); - if (sock_owned_by_user(sk)) { - /* Try again later. */ - icsk->icsk_ack.blocked = 1; - NET_INC_STATS_BH(LINUX_MIB_DELAYEDACKLOCKED); - sk_reset_timer(sk, &icsk->icsk_delack_timer, - jiffies + TCP_DELACK_MIN); - goto out; - } - - if (sk->sk_state == DCCP_CLOSED || - !(icsk->icsk_ack.pending & ICSK_ACK_TIMER)) - goto out; - if (time_after(icsk->icsk_ack.timeout, jiffies)) { - sk_reset_timer(sk, &icsk->icsk_delack_timer, - icsk->icsk_ack.timeout); - goto out; - } - - icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; - - if (inet_csk_ack_scheduled(sk)) { - if (!icsk->icsk_ack.pingpong) { - /* Delayed ACK missed: inflate ATO. */ - icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, - icsk->icsk_rto); - } else { - /* Delayed ACK missed: leave pingpong mode and - * deflate ATO. - */ - icsk->icsk_ack.pingpong = 0; - icsk->icsk_ack.ato = TCP_ATO_MIN; - } - dccp_send_ack(sk); - NET_INC_STATS_BH(LINUX_MIB_DELAYEDACKS); - } -out: - bh_unlock_sock(sk); - sock_put(sk); -} - /* * The DCCP retransmit timer. */ @@ -142,19 +89,11 @@ static void dccp_retransmit_timer(struct sock *sk) struct inet_connection_sock *icsk = inet_csk(sk); /* - * sk->sk_send_head has to have one skb with - * DCCP_SKB_CB(skb)->dccpd_type set to one of the retransmittable DCCP - * packet types (REQUEST, RESPONSE, the ACK in the 3way handshake - * (PARTOPEN timer), etc). - */ - BUG_TRAP(sk->sk_send_head != NULL); - - /* * More than than 4MSL (8 minutes) has passed, a RESET(aborted) was * sent, no need to retransmit, this sock is dead. */ if (dccp_write_timeout(sk)) - goto out; + return; /* * We want to know the number of packets retransmitted, not the @@ -163,29 +102,27 @@ static void dccp_retransmit_timer(struct sock *sk) if (icsk->icsk_retransmits == 0) DCCP_INC_STATS_BH(DCCP_MIB_TIMEOUTS); - if (dccp_retransmit_skb(sk, sk->sk_send_head) < 0) { + if (dccp_retransmit_skb(sk) != 0) { /* * Retransmission failed because of local congestion, * do not backoff. */ - if (icsk->icsk_retransmits == 0) + if (--icsk->icsk_retransmits == 0) icsk->icsk_retransmits = 1; inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, min(icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL), DCCP_RTO_MAX); - goto out; + return; } icsk->icsk_backoff++; - icsk->icsk_retransmits++; icsk->icsk_rto = min(icsk->icsk_rto << 1, DCCP_RTO_MAX); inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto, DCCP_RTO_MAX); - if (icsk->icsk_retransmits > 3 /* FIXME: sysctl_dccp_retries1 */) + if (icsk->icsk_retransmits > sysctl_dccp_retries1) __sk_dst_reset(sk); -out:; } static void dccp_write_timer(unsigned long data) @@ -240,7 +177,7 @@ static void dccp_keepalive_timer(unsigned long data) /* Only process if socket is not in use. */ bh_lock_sock(sk); if (sock_owned_by_user(sk)) { - /* Try again later. */ + /* Try again later. */ inet_csk_reset_keepalive_timer(sk, HZ / 20); goto out; } @@ -253,3 +190,104 @@ out: bh_unlock_sock(sk); sock_put(sk); } + +/* This is the same as tcp_delack_timer, sans prequeue & mem_reclaim stuff */ +static void dccp_delack_timer(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + struct inet_connection_sock *icsk = inet_csk(sk); + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + /* Try again later. */ + icsk->icsk_ack.blocked = 1; + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED); + sk_reset_timer(sk, &icsk->icsk_delack_timer, + jiffies + TCP_DELACK_MIN); + goto out; + } + + if (sk->sk_state == DCCP_CLOSED || + !(icsk->icsk_ack.pending & ICSK_ACK_TIMER)) + goto out; + if (time_after(icsk->icsk_ack.timeout, jiffies)) { + sk_reset_timer(sk, &icsk->icsk_delack_timer, + icsk->icsk_ack.timeout); + goto out; + } + + icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; + + if (inet_csk_ack_scheduled(sk)) { + if (!icsk->icsk_ack.pingpong) { + /* Delayed ACK missed: inflate ATO. */ + icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, + icsk->icsk_rto); + } else { + /* Delayed ACK missed: leave pingpong mode and + * deflate ATO. + */ + icsk->icsk_ack.pingpong = 0; + icsk->icsk_ack.ato = TCP_ATO_MIN; + } + dccp_send_ack(sk); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_DELAYEDACKS); + } +out: + bh_unlock_sock(sk); + sock_put(sk); +} + +/** + * dccp_write_xmitlet - Workhorse for CCID packet dequeueing interface + * See the comments above %ccid_dequeueing_decision for supported modes. + */ +static void dccp_write_xmitlet(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) + sk_reset_timer(sk, &dccp_sk(sk)->dccps_xmit_timer, jiffies + 1); + else + dccp_write_xmit(sk); + bh_unlock_sock(sk); +} + +static void dccp_write_xmit_timer(unsigned long data) +{ + dccp_write_xmitlet(data); + sock_put((struct sock *)data); +} + +void dccp_init_xmit_timers(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + + tasklet_init(&dp->dccps_xmitlet, dccp_write_xmitlet, (unsigned long)sk); + setup_timer(&dp->dccps_xmit_timer, dccp_write_xmit_timer, + (unsigned long)sk); + inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer, + &dccp_keepalive_timer); +} + +static ktime_t dccp_timestamp_seed; +/** + * dccp_timestamp - 10s of microseconds time source + * Returns the number of 10s of microseconds since loading DCCP. This is native + * DCCP time difference format (RFC 4340, sec. 13). + * Please note: This will wrap around about circa every 11.9 hours. + */ +u32 dccp_timestamp(void) +{ + u64 delta = (u64)ktime_us_delta(ktime_get_real(), dccp_timestamp_seed); + + do_div(delta, 10); + return delta; +} +EXPORT_SYMBOL_GPL(dccp_timestamp); + +void __init dccp_timestamping_init(void) +{ + dccp_timestamp_seed = ktime_get_real(); +} |